Females with 3 x chromosomes

Triple X Syndrome

  • Larger text sizeLarge text sizeRegular text size

Triple X syndrome is a genetic condition found in females only. About 1 in 1,000 girls have it.

Girls with triple X syndrome — also known as XXX syndrome, trisomy X, and 47,XXX, — might be taller than other girls. Other symptoms can include problems with spoken language and processing spoken words, coordination problems, and weaker muscles.

Most girls with triple X syndrome can grow up healthy, have normal sexual development and fertility, and lead productive lives.

Depending on which symptoms a girl has and how severe they are, doctors may recommend various treatments.

What Causes Triple X Syndrome?

Girls who have triple X syndrome are born with it. It’s called triple X because they have an extra X chromosome in most or all of their cells.

Usually, a person has 46 chromosomes in each cell, divided into 23 pairs, which includes two sex chromosomes. Half of the chromosomes are inherited from the father and the other half from the mother. The chromosomes contain genes, which determine an individual’s characteristics, such as eye color and height. Girls typically have two X chromosomes (or XX), but girls with triple X syndrome have an extra X chromosome (XXX).

Triple X is not caused by anything the parents did or did not do. The disorder is a random error in cell division. This error can happen before conception in the reproductive cells of the mother or the father, or early in the embryo’s development.

When the extra chromosome is due to incorrect cell division in the embryo, a girl may have a mosaic form of triple X syndrome. This means some of the cells have an extra X chromosome, but not all do. Girls with this type of triple X syndrome usually have fewer symptoms.

What Are the Signs & Symptoms of Triple X Syndrome?

Noticeable signs and symptoms of triple X syndrome can vary greatly. Some girls have no obvious signs, while others have mild symptoms. Occasionally, the disorder causes significant problems.

Girls with triple X syndrome can have some or all of these physical symptoms to some degree:

  • taller than average height (usually, very long legs)
  • low muscle tone, or muscle weakness (called hypotonia)
  • very curved pinky finger (called clinodactyly)
  • widely spaced eyes (called hypertelorism)

Girls with triple X syndrome also may have delayed development of their social, language, and learning skills. They also can have problems with reading and understanding math, and may have mild delays with coordination.

What Problems Can Happen?

Girls with triple X syndrome may develop anxiety, depression, and attention deficit hyperactivity disorder (ADHD). These problems might ease as they get older and reach adulthood. Otherwise, treatment can help manage them.

Less often, girls might have abnormal development of the ovaries and/or uterus, a delayed or early onset of puberty, and problems with fertility. Rarely, a girl may develop kidney and heart problems, frequent urinary tract infections (UTIs), stomach pain, constipation, flat feet, and an abnormally shaped chest wall and ribcage (called pectus excavatum).

How Is Triple X Syndrome Diagnosed?

Many girls with triple X syndrome are healthy and have no obvious symptoms. So sometimes the condition isn’t diagnosed or is only found while a doctor checks for a different issue.

Triple X syndrome often is found because parents talked with a doctor about concerns with their daughter’s development. This can help girls receive a diagnosis early. Research has shown that early interventions and treatments are more effective.

To diagnose triple X syndrome, a blood sample is checked for the presence of the extra X chromosome. Before birth, the condition can be found through a chromosomal analysis. Testing is done on the fluid surrounding the fetus, tissue from the placenta, or the blood from the mother.

How Is Triple X Syndrome Treated?

There is no cure for triple X syndrome, but treatments can help with specific symptoms.

Finding services early is important and can greatly increase their ability to help your daughter live a healthier, more productive life. Options vary greatly depending on how old a girl was when she was diagnosed, whether she has noticeable symptoms, and the severity of those symptoms.

Treatments can include:

Regular doctor visits. At periodic visits, a doctor can monitor a girl’s development for delays, social and language disabilities, or health problems and treat these promptly.

Educational support services. Educational support can teach girls ways to keep pace in school. Some girls might be eligible for an individualized educational program (IEP) or 504 education plan, which are designed to help children with specialized needs.

Early intervention services. It can be very helpful and often more effective for a girl to have speech, occupational, physical, or developmental therapy in the early months of life or as soon as concerns are identified.

Speech therapy and physical therapy can improve your daughter’s speaking, reading, and writing skills and can help increase strength and coordination. Occupational therapy and behavioral therapy can help your daughter develop more confidence and interact better with other children.

Counseling. The whole family can benefit from counseling to better understand triple X syndrome and help a girl who has it to live a productive life.

Early inventions should be considered at infancy for physical therapy, at 15 months for speech delay, at 1st grade for reading and learning issues, and at 3rd grade for anxiety or depression.

Looking Ahead

Girls with triple X syndrome can develop speech, learning, or social challenges at a young age. This can make them more likely to have low self-esteem and lead to school or social problems.

If your daughter has trouble making friends or struggles at school, talk to your doctor or the principal or school counselor. Counseling and therapy can teach your daughter practical skills to help her make friends and feel more confident in school, and educational services can help your daughter succeed academically.

It’s important to speak to your doctor if you have any concerns about your daughter’s physical and emotional development.

Reviewed by: Judith L. Ross, MD Date reviewed: August 2017

About 47,XXX (Trisomy X)

Trisomy X affects approximately 1 in 1,000 females. Girls and women with 47,XXX can be completely symptom-free and unaware of their extra X chromosome, or they can have significant developmental, medical, and psychological issues.

As you can see in the adjoining photo collage of girls and young women with 47,XXX, the condition is not characterized by any prominent physical features. Affected children and adults do not look any different than their peers, though they may be somewhat taller and demonstrate subtle physical attributes including a curved little finger, epicanthal eyelid fold (skin curving slightly down toward the inner eye), and flat feet.

Symptoms

47,XXX may produce the following additional symptoms, although most affected individuals will have only some of them:

  • Low muscle tone
  • Speech delay/expressive language disorder
  • Genito-urinary or kidney malformations
  • Primary ovarian failure
  • Subtle developmental delays
  • Learning disability
  • Attention deficits
  • Depression/anxiety
  • Seizures

Because symptoms are subtle and vary widely from one person to the next, only 30 percent of affected individuals are diagnosed during their lifetimes. Some may be identified prenatally due to maternal testing (amniocentesis, CVS, or non-invasive cell free DNA blood test) for advanced maternal age or other risk factors.

Another point at which 47,XXX may be detected is during infertility testing in adulthood or during non-invasive prenatal testing when the mother’s extra X may be detected during cell-free DNA blood work.

The Case for Testing

One of the goals of AXYS is to encourage families to be aware of the developmental, medical and psychosocial issues that may accompany 47,XXX. Cases involving a history of symptoms such as speech delay, learning disability, developmental problems or genito-urinary malformations should be followed up with genetic testing to determine if the cause is an X and Y variation.

Testing for 47,XXX involves a specialized blood test, either a karyotyping or a microarray. Health care professionals, including physicians, may be unfamiliar with the cognitive, developmental and medical conditions associated with 47,XXX. They often associate genetic syndromes with dysmorphia (characteristic facial or body features) or with intellectual disability, and fail to suggest genetic testing.

Frequently Asked Questions about 47,XXX

Downloadable Brochure- About 47,XXX (Trisomy X)
Trifold brochure printing instructions: Be sure you are printing in two-sided (duplex) mode, and to select the “Flip on Short Edge” or “Short-Edge Binding” option, if available in the Print dialog box or any associated dialog boxes.

Living with Klinefelter Syndrome (47,XXY) Trisomy X (47, XXX) and 47, XYY: A Guide for Families and Individuals Affected by Extra X and Y Chromosome Variations

Thanks to the generosity of the book’s author, Virginia Isaac’s Cover, MSW, AXYS is pleased to make this book available to the X and Y variation community, in its entirety, at no cost. Please feel free to download and/or print it for your personal use. (Those wishing to purchase a soft-bound copy can do so at Amazon or Kindle. All proceeds from the sale of this book benefit AXYS.)

Spanish: “A Guide for Families and Individuals Affected by X and Y Chromosome Variations”

Trisomy X article by Nicole Tartaglia, et al

Spanish language version

Expanding the Phenotype of Triple X Syndrome by Nicole Tartaglia, et al

For Children and Adolescents

Talking to your daughter: “My Guide to Trisomy X

“Elizabeth and her Extra X”

Facebook Support Groups

Trisomy X/Triple X/XXX Global Support Group

Trisomy X- A Group Just For Us

Other Trisomy X Websites

Contactgroep Triple-X Syndroom (The Netherlands)

What Is Triple X Syndrome?

Women with an extra X chromosome in their cells may show no symptoms of this condition.

Triple X syndrome — also called XXX syndrome, trisomy X, or 47,XXX aneuploidy — is a genetic disorder in which a woman carries an extra X chromosome in each of her cells.

Normally, women have two X chromosomes per cell, and men have an X and a Y.

But in triple X syndrome, as its name suggests, three X chromosomes are present.

Sometimes only some of the body’s cells contain the extra X chromosome, a form of triple X syndrome called mosaicism.

Although it’s a genetic disorder, triple X syndrome (which affects only women) is not usually inherited.

Nonetheless, there’s some evidence that the incidence of triple X increases with maternal age (i.e., women who are older when they give birth).

The extra X chromosome usually results from random error when the parents’ egg or sperm cell is forming.

In mosaicism, the error happens during cell division early in the fetus’s development.

How Common Is Triple X Syndrome?

While triple X syndrome is rare, it might not be as rare as the numbers would suggest.

In the most frequently cited statistic, triple X occurs in about one out of every 1,000 female births, meaning that five to 10 females are born with triple X syndrome each day in the United States.

But since many girls and women show no or very mild symptoms of triple X, some researchers estimate that only 10 percent of the cases are ever diagnosed and that the actual numbers are higher.

Triple X Syndrome Symptoms

While the symptoms and physical characteristics associated with triple X syndrome vary widely among girls and women — with some displaying no symptoms or unusual physical characteristics — tall stature is the most common trait.

Other physical, developmental, and behavioral characteristics associated with triple X syndrome include:

  • Skin folds that descend and cover the inner corners of the eyes
  • Wide spacing between the eyes
  • Decreased muscle tone (hypotonia)
  • Curved fifth (“pinky”) fingers (clinodactyly)
  • Small head circumference
  • Lower average birth weight
  • Learning disabilities, such as delayed speech and language development, and difficulty reading
  • Delayed motor skills, such as sitting and walking
  • Problems processing sound
  • Behavioral and emotional problems, including attention deficit hyperactivity disorder (ADHD), anxiety, and depression
  • Premature ovarian failure or ovary malformations (though infertility is rare)
  • Menstrual irregularities
  • Constipation or abdominal pains
  • Flat feet
  • Mild concavity of the breastbone

In the mosaic form of triple X syndrome, fewer cells have the extra X chromosome, so symptoms and characteristics, when they are present, are more mild.

Seizures or kidney abnormalities (such as having a single kidney, or a malformed one), are possible in triple X but rare — they show up in about 10 percent of cases.

Most girls and women with triple X syndrome are usually of normal intelligence, but IQ scores, especially verbal scores, tend to be 10 to 15 points below that of siblings or those in control groups, according to the National Organization for Rare Disorders (NORD), especially if learning disabilities are not addressed early.

Heart abnormalities have been noted in some isolated cases, according to NORD.

Triple X Syndrome Diagnosis

Triple X syndrome can be diagnosed prenatally, through CVS (chorionic villus sampling, in which tissue samples are taken from the placenta) or through amniocentesis.

The condition can also be diagnosed through a post-birth blood test if developmental delays, poor muscle tone, or other physical characteristics associated with triple X prompt a doctor to suspect it.

Triple X Syndrome Treatment

While the extra X chromosome can of course never be removed, early intervention, such as speech or physical therapy, can help, as well as counseling as girls enter middle school and adolescence.

Early screening for kidney and heart abnormalities, which although rare are possible in triple X, is also recommended.

Women who experience late periods, menstrual abnormalities, or who have difficulty conceiving should be evaluated for primary ovarian failure.

What is triple X syndrome?

Everything that lives has genes. Genes are a set of instructions that decide what the organism is like, how it survives, and how it behaves in its environment. Genes occur in long strands of DNA called chromosomes. Chromosomes are found in virtually all the cells of the body. Genes decide whether a person will be male or female, tall or short, and what color their hair and skin will be. They also affect the risk of developing certain diseases, and how an individual responds to environmental triggers.

Humans have 23 pairs of chromosomes, or a total of 46. A donkey has 31 pairs of chromosomes, a hedgehog has 44, and a fruit fly has just 4.

One of these 23 chromosome pairs in a human determines whether the person will be a man or a woman. Each person receives one sex chromosome from their mother and one from their father.

Females have an XX pair, so a mother can only pass on an X chromosome. Males have an XY pair, so a father can pass on either an X or a Y chromosome.

If a fetus receives an X chromosome from the father, she will be female, because the mother will pass on an X chromosome. This will give her an XX chromosome pair.

If the father passes on a Y chromosome, the offspring will have an XY chromosome pair, making him a male. Individuals with triple X syndrome have an extra X chromosome, as well as the XX pair. In other words, they are females (XX) with an extra X chromosome (XXX).

Reasons why this might occur are:

  • The mother’s egg was not formed properly, known as nondisjunction – all cells will be XXX.
  • The father’s sperm was not formed properly, also called nondisjunction – all cells will be XXX.
  • A problem occurred while the embryo was developing. This is referred to as a mosaic form – not all cells will be XXX.

Triple X syndrome is not an inherited condition.

If the syndrome is caused by a badly formed egg or sperm, every cell in the body has the extra chromosome. In the mosaic form of triple X syndrome, only a certain number of body cells have the extra chromosome. Symptoms will depend partly on how many body cells have the extra X chromosome.

Most cases of triple X syndrome are caused by a malformed egg or sperm. Triple X syndrome is sometimes called 47 XXX syndrome because the extra chromosome gives the person 47 chromosomes, instead of the usual 46.

  1. 1

    Gustavson KH : Triple X syndrome deviation with mild symptoms. The majority goes undiagnosed. Lakartidningen 1999; 96: 5646–5647.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  2. 2

    Jacobs PA : The incidence and etiology of sex chromosome abnormalities in man. Birth Defects Orig Artic Ser 1979; 15: 3–14.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  3. 3

    Robinson A, Linden MG, Bender BG : Prenatal diagnosis of sex chromosomal abnormalities. In: Milunsky A (ed): Genetic Disorders and the Fetus; Diagnosis, Prevention and Treatment, 4th edn Baltimore and London: Johns Hopkins, 1998, pp 249–285.

    • Google Scholar
  4. 4

    Lejeune J, Gautier M, Turpin R : Study of somatic chromosomes from 9 mongoloid children. C R Hebd Seances Acad Sci 1959; 248: 1721–1722.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  5. 5

    Jacobs PA, Strong JA : A case of human intersexuality having a possible XXY sex-determining mechanism. Nature 1959; 183: 302–303.

    • CAS
    • Google Scholar
  6. 6

    Ford CE, Jones KW, Polani PE, De Almeida JC, Briggs JH : A sex-chromosome anomaly in a case of gonadal dysgenesis (Turner’s syndrome). Lancet 1959; 273: 711–713.

    • Google Scholar
  7. 7

    Jacobs PA, Baikie AG, Court Brown WM, MacGregor TN, Maclean N, Harnden DG : Evidence for the existence of the human ‘super female’. Lancet 1959; 274: 423–425.

    • Google Scholar
  8. 8

    Levitas AS, Reid CS : An angel with Down syndrome in a sixteenth century Flemish Nativity painting. Am J Med Genet A 2003; 116: 399–405.

    • Google Scholar
  9. 9

    Brain L : Historical introduction. In: Wolstenholme GEW, Porter R (eds): Mongolism: In Commemoration of Dr John Langdon Haydon Down. Boston: Little, Brown and Company, 1967, pp 1–5.

    • Google Scholar
  10. 10

    Klinefelter HF, Reifenstein EC, Albright F : Syndrome characterised by gynaecomastia, aspermatogenesis, without, A-leydigism and increased excretion of follicle-stimulating hormone. J Clin Endocrinol 1942; 2: 615–627.

    • CAS
    • Google Scholar
  11. 11

    Turner HH : A syndrome of infantilism, congenital webbed neck and cubitus valgus. Endocrinology 1938; 23: 566–574.

    • Google Scholar
  12. 12

    Nielsen J : Triple-X females. An orientation, 1989, available at http://www.turnercenteret.dk/engelsk/triplex.htm.

  13. 13

    Barr ML, Sergovich FR, Carr DH, Saver EL : The triplo-X female: an appraisal based on a study of 12 cases and a review of the literature. Can Med Assoc J 1969; 101: 247–258.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  14. 14

    Guichet A, Briault S, Moraine C, Turleau C : Trisomy X: ACLF (Association des Cytogeneticiens de Langue Francaise) retrospective study. Ann Genet 1996; 39: 117–122.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  15. 15

    Robinson A, Lubs HA, Bergsma D : Sex chromosome aneuploidy: prospective studies on children. Birth Defects Orig Artic Ser 1979; 15: 1–281.

    • Google Scholar
  16. 16

    Stewart DA : Children with sex chromosome aneuploidy: follow-up studies. Birth Defects Orig Artic Ser 1982; 18: 1–251.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  17. 17

    Ratcliffe SG, Paul N : Prospective studies on children with sex chromosome aneuploidy. Birth Defects Orig Artic Ser 1986; 22: 1–328.

    • Google Scholar
  18. 18

    Evans JA, Hamerton JL, Robinson A : Children and young adults with sex chromosome aneuploidy. Birth Defects Orig Artic Ser 1990; 26: 1–312.

    • Google Scholar
  19. 19

    Robinson A, Lubs HA, Nielsen J, Sorensen K : Summary of clinical findings: profiles of children with 47,XXY, 47,XXX and 47,XYY karyotypes. Birth Defects Orig Artic Ser 1979; 15: 261–266.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  20. 20

    Stewart DA, Netley CT, Park E : Summary of clinical findings of children with 47,XXY, 47,XYY, and 47,XXX karyotypes. Birth Defects Orig Artic Ser 1982; 18: 1–5.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  21. 21

    Netley CT : Summary overview of behavioural development in individuals with neonatally identified X and Y aneuploidy. Birth Defects Orig Artic Ser 1986; 22: 293–306.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  22. 22

    Robinson A, Bender BG, Linden MG : Summary of clinical findings in children and young adults with sex chromosome anomalies. Birth Defects Orig Artic Ser 1990; 26: 225–228.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  23. 23

    Gilgenkrantz S, Gilgenkrantz JM, Streiff F, Fauchier JP, Baillon D : Syndrome triplo X et anomalies squelettiques. Ann Med Nancy 1967; 6: 172–186.

    • Google Scholar
  24. 24

    Pfeiffer RA, Palm D, Jochmus J : . Monatsschr Kinderheilkd 1967; 115: 9–18.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  25. 25

    Polani PE : Abnormal sex chromosomes, behaviour and mental disorder; in Tanner JM (ed): Developments in Psychiatric Research. London: Mental Health Foundation, 1977, pp 89–128.

    • Google Scholar
  26. 26

    Olanders S : Females with Supernumerary X Chromosomes; A Study of 39 Psychiatric Cases. Göteborg: University of Göteborg, 1975.

    • Google Scholar
  27. 27

    Gotz M : The Psychiatric Consequences of Sex Chromosome Abnormalities: A Cohort Study. Edinburgh: University of Edinburgh, 1996.

    • Google Scholar
  28. 28

    Warwick MM : Brain Morphology and Personality Characteristics of Subjects with Sex Chromosome Anomalies and Matched Controls. Edinburgh: University of Edinburgh, 1999.

    • Google Scholar
  29. 29

    Penrose LS : Review of WM Court Brown, editor, Abnormalities of the sex chromosome complement in man. Ann Hum Genet 1964; 28: 199–200.

    • Google Scholar
  30. 30

    Bender BG, Linden MG, Harmon RJ : Neuropsychological and functional cognitive skills of 35 unselected adults with sex chromosome abnormalities. Am J Med Genet 2001; 102: 309–313.

    • CAS
    • Google Scholar
  31. 31

    Bender BG, Linden MG, Harmon RJ : Life adaptation in 35 adults with sex chromosome abnormalities. Genet Med 2001; 3: 187–191.

    • CAS
    • Google Scholar
  32. 32

    Linden MG, Bender BG : Fifty-one prenatally diagnosed children and adolescents with sex chromosome abnormalities. Am J Med Genet 2002; 110: 11–18.

    • Google Scholar
  33. 33

    Robinson A : Introduction. Birth Defects Orig Artic Ser 1979; 15: 1–2.

    • Google Scholar
  34. 34

    Leschot NJ, Verjaal M, Treffers PE : A critical analysis of 75 therapeutic abortions. Early Hum Dev 1985; 10: 287–293.

    • CAS
    • Google Scholar
  35. 35

    Krone LR, Prichard LL, Bradshaw CL, Jones OW, Peterson RM, Dixson BK : Antenatal diagnosis of an XXX female. A dilemma for genetic counseling. West J Med 1975; 123: 17–21.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  36. 36

    Mueller-Heubach E, Garver KL, Ciocco AM : Prenatal diagnosis of trisomy X: its implications for genetic counseling. Am J Obstet Gynecol 1977; 127: 211–212.

    • CAS
    • Google Scholar
  37. 37

    Ratcliffe SG, Axworthy D, Ginsborg A : The Edinburgh study of growth and development in children with sex chromosome abnormalities. Birth Defects Orig Artic Ser 1979; 15: 243–260.

    • CAS
    • Google Scholar
  38. 38

    Olanders S : Somatic findings. In: Olanders S (ed): Females with Supernumerary X Chromosomes; A Study of 39 Psychiatric Cases. Göteborg: University of Göteborg, 1975, pp 41–60.

    • Google Scholar
  39. 39

    Olanders S : Case histories. In: Olanders S (ed): Females with Supernumerary X Chromosomes; A Study of 39 Psychiatric Cases. Göteborg: University of Göteborg, 1975, pp 108–204.

    • Google Scholar
  40. 40

    Emerit I, de Grouchy J, Vernant P, Corone P : Chromosomal abnormalities and congenital heart disease. Circulation 1967; 36: 886–905.

    • CAS
    • Google Scholar
  41. 41

    Fixler DE : Epidemiology of Congenital Heart Disease; in McMillan JA, Feigin RD, DeAngelis C, Jones MD (eds): Oski’s Principles & Practice of Pediatrics. Philadelphia: Lippincott Williams & Wilkins, 2006, pp 335–338.

    • Google Scholar
  42. 42

    Francois J, Berger JFR, Saraux H : Anomalies des chromosomes sexuels; Trisomie X; in: Francois J, Berger JFR, Saraux H (eds): Les Aberrations Chromosomiques En Ophtalmologie. Paris: Masson & Cie, 1972, pp 389–394.

    • Google Scholar
  43. 43

    Haverty CE, Lin AE, Simpson E, Spence MA, Martin RA : 47,XXX associated with malformations. Am J Med Genet A 2004; 125: 108–111.

    • Google Scholar
  44. 44

    Ratcliffe S : Long-term outcome in children of sex chromosome abnormalities. Arch Dis Child 1999; 80: 192–195.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  45. 45

    Smith HC, Seale JP, Posen S : Premature ovarian failure in a triple X female. J Obstet Gynaecol Br Commonw 1974; 81: 405–409.

    • CAS
    • Google Scholar
  46. 46

    Castillo S, Lopez F, Tobella L, Salazar S, Daher V : The cytogenetics of premature ovarian failure. Rev Chil Obstet Ginecol 1992; 57: 341–345.

    • CAS
    • Google Scholar
  47. 47

    Holland C : 47,XXX in an adolescent with premature ovarian failure and autoimmune disease. J Pediatr Adolesc Gynecol 2000; 13: 93.

    • CAS
    • Google Scholar
  48. 48

    Goswami R, Goswami D, Kabra M, Gupta N, Dubey S, Dadhwal V : Prevalence of the triple X syndrome in phenotypically normal women with premature ovarian failure and its association with autoimmune thyroid disorders. Fertil Steril 2003; 80: 1052–1054.

    • Google Scholar
  49. 49

    Olanders S, Selldén U : Electroencephalografic investigation; in Olanders S (ed): Females with Supernumerary X Chromosomes; A Study of 39 Psychiatric Cases. Göteborg, Sweden: University of Göteborg, 1975, pp 77–85.

    • Google Scholar
  50. 50

    Grosso S, Farnetani MA, Di Bartolo RM et al: Electroencephalographic and epileptic patterns in X chromosome anomalies. J Clin Neurophysiol 2004; 21: 249–253.

    • Google Scholar
  51. 51

    Roubertie A, Humbertclaude V, Leydet J, Lefort G, Echenne B : Partial epilepsy and 47,XXX karyotype: report of four cases. Pediatr Neurol 2006; 35: 69–74.

    • Google Scholar
  52. 52

    Olanders S : Other psychiatric findings; in Olanders S (ed): Females with Supernumerary X Chromosomes; A Study of 39 Psychiatric Cases. Göteborg, University of Göteborg, 1975, pp 91–104.

    • Google Scholar
  53. 53

    Woodhouse WJ, Holland AJ, McLean G, Reveley AM : The association between triple X and psychosis. Br J Psychiatry 1992; 160: 554–557.

    • CAS
    • Google Scholar
  54. 54

    Kanaka-Gantenbein C, Kitsiou S, Mavrou A et al: Tall stature, insulin resistance, and disturbed behavior in a girl with the triple X syndrome harboring three SHOX genes: offspring of a father with mosaic Klinefelter syndrome but with two maternal X chromosomes. Horm Res 2004; 61: 205–210.

    • CAS
    • Google Scholar
  55. 55

    Nielsen J, Sillesen I, Sorensen AM, Sorensen K : Follow-up until age 4–8 of 25 unselected children with sex chromosome abnormalities, compared with sibs and controls. Birth Defects Orig Artic Ser 1979; 15: 15–73.

    • CAS
    • Google Scholar
  56. 56

    Stewart DA, Netley CT, Bailey JD et al: Growth and development of children with X and Y chromosome aneuploidy: a prospective study. Birth Defects Orig Artic Ser 1979; 15: 75–114.

    • CAS
    • Google Scholar
  57. 57

    Robinson A, Puck M, Pennington B, Borelli J, Hudson M : Abnormalities of the sex chromosomes: a prospective study on randomly identified newborns. Birth Defects Orig Artic Ser 1979; 15: 203–241.

    • CAS
    • Google Scholar
  58. 58

    Stewart DA, Bailey JD, Netley CT et al: Growth and development of children with X and Y chromosome aneuploidy from infancy to pubertal age: the Toronto study. Birth Defects Orig Artic Ser 1982; 18: 99–154.

    • CAS
    • Google Scholar
  59. 59

    Leonard MF, Sparrow S, Schowalter JE : A prospective study of development of children with sex chromosome anomalies – New Haven study III. The middle years. Birth Defects Orig Artic Ser 1982; 18: 193–218.

    • CAS
    • Google Scholar
  60. 60

    Ratcliffe SG, Masera N, Pan H, McKie M : Head circumference and IQ of children with sex chromosome abnormalities. Dev Med Child Neurol 1994; 36: 533–544.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  61. 61

    Nielsen J, Sorensen AM, Sorensen K : Follow-up until age 7–11 of 25 unselected children with sex chromosome abnormalities. Birth Defects Orig Artic Ser 1982; 18: 61–97.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  62. 62

    Ratcliffe SG, Tierney I, Nshaho J, Smith L, Springbett A, Callan S : The Edinburgh study of growth and development of children with sex chromosome abnormalities. Birth Defects Orig Artic Ser 1982; 18: 41–60.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  63. 63

    Hreczko TA, Sigmon BA : The dermatoglyphics of a Toronto sample of children with XXY, XXYY, and XXX aneuploidies. Am J Phys Anthropol 1980; 52: 33–41.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  64. 64

    Bender B, Fry E, Pennington B, Puck M, Salbenblatt J, Robinson A : Speech and language development in 41 children with sex chromosome anomalies. Pediatrics 1983; 71: 262–267.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  65. 65

    Robinson A, Bender B, Borelli J, Puck M, Salbenblatt J, Webber ML : Sex chromosomal abnormalities (SCA): a prospective and longitudinal study of newborns identified in an unbiased manner. Birth Defects Orig Artic Ser 1982; 18: 7–39.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  66. 66

    Evans JA, de von Flindt R, Greenberg C, Ramsay S, Hamerton JL : A cytogenetic survey of 14 069 newborn infants. IV. Further follow-up on the children with sex chromosome anomalies. Birth Defects Orig Artic Ser 1982; 18: 169–184.

    • CAS
    • Google Scholar
  67. 67

    Stewart DA, Bailey JD, Netley CT, Rovet J, Park E : Growth and development from early to midadolescence of children with X and Y chromosome aneuploidy: the Toronto Study. Birth Defects Orig Artic Ser 1986; 22: 119–182.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  68. 68

    Ratcliffe SG, Murray L, Teague P : Edinburgh study of growth and development of children with sex chromosome abnormalities. III. Birth Defects Orig Artic Ser 1986; 22: 73–118.

    • CAS
    • Google Scholar
  69. 69

    Linden MG, Bender BG, Harmon RJ, Mrazek DA, Robinson A : 47,XXX: what is the prognosis? Pediatrics 1988; 82: 619–630.

    • CAS
    • Google Scholar
  70. 70

    Robinson A, Bender BG, Linden MG, Salbenblatt JA : Sex chromosome aneuploidy: the Denver Prospective Study. Birth Defects Orig Artic Ser 1990; 26: 59–115.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  71. 71

    Bender BG, Linden M, Robinson A : Cognitive and academic skills in children with sex chromosome abnormalities. Read Writ 1991; 3: 315–327.

    • Google Scholar
  72. 72

    Bender BG, Linden MG, Robinson A : Neuropsychological impairment in 42 adolescents with sex chromosome abnormalities. Am J Med Genet 1993; 48: 169–173.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  73. 73

    Bender BG, Harmon RJ, Linden MG, Robinson A : Psychosocial adaptation of 39 adolescents with sex chromosome abnormalities. Pediatrics 1995; 96: 302–308.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  74. 74

    Bender BG, Harmon RJ, Linden MG, Bucher-Bartelson B, Robinson A : Psychosocial competence of unselected young dults with sex chromosome abnormalities. Am J Med Genet 1999; 88: 200–206.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  75. 75

    Linden MG, Bender BG, Robinson A : Genetic counseling for sex chromosome abnormalities. Am J Med Genet 2002; 110: 3–10.

    • PubMed
    • PubMed Central
    • Google Scholar
  76. 76

    Warwick MM, Doody GA, Lawrie SM, Kestelman JN, Best JJ, Johnstone EC : Volumetric magnetic resonance imaging study of the brain in subjects with sex chromosome aneuploidies. J Neurol Neurosurg Psychiatry 1999; 66: 628–632.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  77. 77

    Patwardhan AJ, Brown WE, Bender BG, Linden MG, Eliez S, Reiss AL : Reduced size of the amygdala in individuals with 47,XXY and 47,XXX karyotypes. Am J Med Genet 2002; 114: 93–98.

    • PubMed
    • PubMed Central
    • Google Scholar
  78. 78

    Stewart JS, Sanderson AR : Fertility and oligophrenia in an apparent triplo-X female. Lancet 1960; 276: 21–23.

    • Google Scholar
  79. 79

    Fraser JH, Campbell J, MacGillivray RC, Boyd E, Lennox B : The XXX syndrome frequency among mental defectives and fertility. Lancet 1960; 276: 626–627.

    • Google Scholar
  80. 80

    Holland CM : 47,XXX in an adolescent with premature ovarian failure and autoimmune disease. J Pediatr Adolesc Gynecol 2001; 14: 77–80.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  81. 81

    Hambert G : Males with Positive Sex Chromatin; An Epidemiologic Investigation Followed by Psychiatric Study of Seventy-Five Cases. Göteborg, University of Göteborg, 1966.

    • Google Scholar
  82. 82

    Gotz M : Results of the present study: XXX women; in Gotz M (ed): The Psychiatric Consequences of Sex Chromosome Abnormalities: A Cohort Study. Edinburgh: University of Edinburgh, 1996, pp 62–68.

    • Google Scholar
  83. 83

    Warwick MM : Discussion; in Warwick MM (ed): Brain Morphology and Personality Characteristics of Subjects with Sex Chromosome Anomalies and Matched Controls. Edinburgh: University of Edinburgh, 1999, pp 75–105.

    • Google Scholar
  84. 84

    Harmon RJ, Bender BG, Linden MG, Robinson A : Transition from adolescence to early adulthood: adaptation and psychiatric status of women with 47,XXX. J Am Acad Child Adolesc Psychiatry 1998; 37: 286–291.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  85. 85

    Robinson A, Bender BG, Linden MG : Prognosis of prenatally diagnosed children with sex chromosome aneuploidy. Am J Med Genet 1992; 44: 365–368.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  86. 86

    Tsuang MT : Sex chromatin anomaly in Chinese females: psychiatric characteristics of XXX. Br J Psychiatry 1974; 124: 299–305.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  87. 87

    Oduncu FS : The role of non-directiveness in genetic counseling. Med Health Care Philos 2002; 5: 53–63.

    • PubMed
    • PubMed Central
    • Google Scholar
  88. 88

    Abramsky L, Hall S, Levitan J, Marteau TM : What parents are told after prenatal diagnosis of a sex chromosome abnormality: interview and questionnaire study. Br Med J 2001; 322: 463–466.

    • CAS
    • Google Scholar
  89. 89

    Farsides B, Williams C, Alderson P : Aiming towards ‘moral equilibrium’: health care professionals’ views on working within the morally contested field of antenatal screening. J Med Ethics 2004; 30: 505–509.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  90. 90

    Forrester MB, Merz RD : Pregnancy outcome and prenatal diagnosis of sex chromosome abnormalities in Hawaii, 1986–1999. Am J Med Genet A 2003; 119: 305–310.

    • Google Scholar
  91. 91

    Nagel HT, Knegt AC, Kloosterman MD, Wildschut HI, Leschot NJ, Vandenbussche FP : . Ned Tijdschr Geneeskd 2004; 148: 1538–1543.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  92. 92

    De Vigan C, Baena N, Cariati E, Clementi M, Stoll C : Contribution of ultrasonographic examination to the prenatal detection of chromosomal abnormalities in 19 centres across Europe. Ann Genet 2001; 44: 209–217.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  93. 93

    Marteau T, Drake H, Reid M et al: Counselling following diagnosis of fetal abnormality: a comparison between German, Portuguese and UK geneticists. Eur J Hum Genet 1994; 2: 96–102.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  94. 94

    Wertz DC, Fletcher JC : Genetics and Ethics in Global Perspective. Dordrecht: Kluwer Academic Publishers, 2004.

    • Google Scholar
  95. 95

    Sagi M, Meiner V, Reshef N, Dagan J, Zlotogora J : Prenatal diagnosis of sex chromosome aneuploidy: possible reasons for high rates of pregnancy termination. Prenat Diagn 2001; 21: 461–465.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  96. 96

    Meschede D, Louwen F, Nippert I, Holzgreve W, Miny P, Horst J : Low rates of pregnancy termination for prenatally diagnosed Klinefelter syndrome and other sex chromosome polysomies. Am J Med Genet 1998; 80: 330–334.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  97. 97

    Hashiloni-Dolev Y : Genetic counseling for sex chromosome anomalies (SCAs) in Israel and Germany: assessing medical risks according to the importance of fertility in two cultures. Med Anthropol Q 2006; 20: 469–486.

    • PubMed
    • PubMed Central
    • Google Scholar
  98. 98

    Robinson A, Bender BG, Linden MG : Decisions following the intrauterine diagnosis of sex chromosome aneuploidy. Am J Med Genet 1989; 34: 552–554.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  99. 99

    Linden MG, Bender BG, Robinson A : Intrauterine diagnosis of sex chromosome aneuploidy. Obstet Gynecol 1996; 87: 468–475.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  100. 100

    Vaknin Z, Reish O, Ben-Ami I, Heyman E, Herman A, Maymon R : Prenatal diagnosis of sex chromosome abnormalities: the 8-year experience of a single medical center. Fetal Diagn Ther 2008; 23: 76–81.

    • PubMed
    • PubMed Central
    • Google Scholar
  101. 101

    Shaw SW, Chueh HY, Chang SD, Cheng PJ, Hsieh TT, Soong YK : Parental decisions regarding prenatally detected fetal sex chromosomal abnormality and the impact of genetic counselling: An analysis of 57 cases in Taiwan. Aust N Z J Obstet Gynaecol 2008; 48: 155–159.

    • PubMed
    • PubMed Central
    • Google Scholar
  102. 102

    Chiat S, Roy P : Early phonological and sociocognitive skills as predictors of later language and social communication outcomes. J Child Psychol Psychiatry 2008; 49: 635–645.

    • PubMed
    • PubMed Central
    • Google Scholar
  103. 103

    Lanfranco F, Kamischke A, Zitzmann M, Nieschlag E : Klinefelter’s syndrome. Lancet 2004; 364: 273–283.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  104. 104

    Stahl SM : Sex and psychopharmacology: is natural estrogen a psychotropic drug in women? Arch Gen Psychiatry 2001; 58: 537–538.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  105. 105

    Amin Z, Canli T, Epperson CN : Effect of estrogen-serotonin interactions on mood and cognition. Behav Cogn Neurosci Rev 2005; 4: 43–58.

    • PubMed
    • PubMed Central
    • Google Scholar
  106. 106

    Walf AA, Frye CA : A review and update of mechanisms of estrogen in the hippocampus and amygdala for anxiety and depression behavior. Neuropsychopharmacology 2006; 31: 1097–1111.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  107. 107

    Kulkarni J, de Castella A, Fitzgerald PB et al: Estrogen in severe mental illness: a potential new treatment approach. Arch Gen Psychiatry 2008; 65: 955–960.

    • PubMed
    • PubMed Central
    • Google Scholar
  108. 108

    Frances AJ : Diagnostic and Statistical Manual of Mental Disorders, DSM-IV-TR, 4th edn (text revision edn) Washington, DC: American Psychiatric Association, 2000.

    • Google Scholar
  109. 109

    Thewissen V, Myin-Germeys I, Bentall R, de Graaf R, Vollebergh W, van Os J : Instability in self-esteem and paranoia in a general population sample. Soc Psychiatry Psychiatr Epidemiol 2007; 42: 1–5.

    • PubMed
    • PubMed Central
    • Google Scholar
  110. 110

    Thewissen V, Bentall RP, Lecomte T, van Os J, Myin-Germeys I : Fluctuations in self-esteem and paranoia in the context of daily life. J Abnorm Psychol 2008; 117: 143–153.

    • PubMed
    • PubMed Central
    • Google Scholar
  111. 111

    Crow TJ : Sex chromosomes and psychosis. The case for a pseudoautosomal locus. Br J Psychiatry 1988; 153: 675–683.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  112. 112

    DeLisi LE, Friedrich U, Wahlstrom J et al: Schizophrenia and sex chromosome anomalies. Schizophr Bull 1994; 20: 495–505.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  113. 113

    Penrose LS : Finger-print pattern and the sex chromosomes. Lancet 1967; 289: 298–300.

    • Google Scholar
  114. 114

    Barlow PW : The influence of inactive chromosomes on human development. Anomalous sex chromosome complements and the phenotype. Humangenetik 1973; 17: 105–136.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  115. 115

    Barlow PW : X-chromosomes and human development. Dev Med Child Neurol 1973; 15: 205–208.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  116. 116

    Netley CT, Rovet J : Verbal deficits in children with 47,XXY and 47,XXX karyotypes: a descriptive and experimental study. Brain Lang 1982; 17: 58–72.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  117. 117

    Barlow PW : Differential cell division in human X chromosome mosaics. Humangenetik 1972; 14: 122–127.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  118. 118

    Kaback MM, Bernstein LH : Biologic studies of trisomic cells grown in vitro. Ann N Y Acad Sci 1970; 171: 526–536.

    • Google Scholar
  119. 119

    Torres EM, Sokolsky T, Tucker CM et al: Effects of aneuploidy on cellular physiology and cell division in haploid yeast. Science 2007; 317: 916–924.

    • CAS
    • PubMed
    • Google Scholar
  120. 120

    Francis D, Davies MS, Barlow PW : A strong nucleotypic effect on the cell cycle regardless of ploidy level. Ann Bot (Lond) 2008; 101: 747–757.

    • CAS
    • Google Scholar
  121. 121

    Eisch AJ : Adult neurogenesis: implications for psychiatry. Prog Brain Res 2002; 138: 315–342.

    • PubMed
    • PubMed Central
    • Google Scholar
  122. 122

    McCurdy RD, Feron F, Perry C et al: Cell cycle alterations in biopsied olfactory neuroepithelium in schizophrenia and bipolar I disorder using cell culture and gene expression analyses. Schizophr Res 2006; 82: 163–173.

    • PubMed
    • PubMed Central
    • Google Scholar
  123. 123

    Dranovsky A, Hen R : DISC1 Puts the Brakes on Neurogenesis. Cell 2007; 130: 981–983.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  124. 124

    Duan X, Chang JH, Ge S et al: Disrupted-in-schizophrenia 1 regulates integration of newly generated neurons in the adult brain. Cell 2007; 130: 1146–1158.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  125. 125

    Chubb JE, Bradshaw NJ, Soares DC, Porteous DJ, Millar JK : The DISC locus in psychiatric illness. Mol Psychiatry 2008; 13: 36–64.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  126. 126

    Zhao M, Momma S, Delfani K et al: Evidence for neurogenesis in the adult mammalian substantia nigra. Proc Natl Acad Sci USA 2003; 100: 7925–7930.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  127. 127

    Kempermann G : Adult Neurogenesis; Stem Cells and Neuronal Development in the Adult Brain. New York: Oxford University Press, 2006.

    • Google Scholar
  128. 128

    Migeon BR : Females are MOSAICS; X Inactivation and Sex Differences in Disease. New York: Oxford University Press, 2007.

    • Google Scholar
  129. 129

    Lyon MF : No longer ‘all-or-none’. Eur J Hum Genet 2005; 13: 796–797.

    • PubMed
    • PubMed Central
    • Google Scholar
  130. 130

    Latham KE : X chromosome imprinting and inactivation in preimplantation mammalian embryos. Trends Genet 2005; 21: 120–127.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  131. 131

    Carrel L, Willard HF : X-inactivation profile reveals extensive variability in X-linked gene expression in females. Nature 2005; 434: 400–404.

    • CAS
    • Google Scholar
  132. 132

    Vawter MP, Harvey PD, DeLisi LE : Dysregulation of X-linked gene expression in Klinefelter’s syndrome and association with verbal cognition. Am J Med Genet B Neuropsychiatr Genet 2007; 144: 728–734.

    • PubMed
    • PubMed Central
    • Google Scholar
  133. 133

    Migeon BR, Lee CH, Chowdhury AK, Carpenter H : Species differences in TSIX/Tsix reveal the roles of these genes in X-chromosome inactivation. Am J Hum Genet 2002; 71: 286–293.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  134. 134

    Chiurazzi P, Schwartz CE, Gecz J, Neri G : XLMR genes: update 2007. Eur J Hum Genet 2008; 16: 422–434.

    • CAS
    • PubMed
    • PubMed Central
    • Google Scholar
  135. 135

    Ruppenthal GC, Caffery SA, Goodlin BL, Sackett GP, Vigfusson NV, Peterson VG : Pigtailed macaques (Macaca nemestrina) with trisomy X manifest physical and mental retardation. Am J Ment Defic 1983; 87: 471–476.

    • CAS
    • Google Scholar
  136. 136

    Moreno-Millan M, Delgado Bermejo JV, Lopez Castillo G : An intersex horse with X chromosome trisomy. Vet Rec 1989; 124: 169–170.

    • CAS
    • Google Scholar
  137. 137

    Endo A, Watanabe T : A case of X-trisomy in the mouse. Cytogenet Cell Genet 1989; 52: 98–99.

    • CAS
    • Google Scholar
  138. 138

    Di Meo GP, Perucatti A, Di Palo R et al: Sex chromosome abnormalities and sterility in river buffalo. Cytogenet Genome Res 2008; 120: 127–131.

    • CAS
    • Google Scholar
  139. 139

    Firth HV, Hurst JA : 47,XXX. In: Firth HV, Hurst JA, Hall JG (eds): Oxford Desk Reference Clinical Genetics. Oxford: Oxford University Press, 2005, p 494.

    • Google Scholar

Triple X Syndrome

  • Entry
  • Reader’s Guide
  • Entries A-Z
  • Subject Index
  • Typically, humans have 23 pairs of chromosomes. Women with triple X syndrome, as the name implies, have an extra X chromosome. This creates a chromosome constitution of 47,XXX instead of the characteristic 46,XX. This chromosomal change is typically a random event that occurs during cell division; triple X syndrome is not an inherited condition. Triple X syndrome, also known as trisomy X or XXX syndrome, is diagnosed through genetic karyotyping, a test to identify the number of and changes to chromosomes. This entry describes how triple X syndrome is manifested across the lifespan in women who are affected.

    Triple X syndrome was first described by cytogeneticist Patricia Jacobs in 1959. Jacobs was asked to look at the chromosome structure of a woman who had stopped menses …

    Looks like you do not have access to this content.

    Login

    Don’t know how to login?

    Click here for free trial login.

    • Assessment and Diagnosis
      • Diagnostic and Statistical Manual of Mental Disorders
      • International Classification of Diseases, 10th Revision
      • International Classification of Diseases, History of
      • Academic Achievement Tests
      • Adaptive Behavior Assessment System
      • Adults With Autism Spectrum Disorder
      • Assessment of the Very Young Child
      • Attention-Deficit/Hyperactivity Disorder: Assessment of Children With
      • Autism Diagnostic Interview-Revised
      • Autism Diagnostic Observation Schedule
      • Autism Rating Scales
      • Autism Spectrum Disorder: Assessment in Schools
      • Autism Spectrum Disorder: Assessment of Adults With
      • Autism Spectrum Disorder: Assessment of Comorbid Psychiatric Conditions
      • Autism Spectrum Disorder: Assessment of Social Behavior
      • Autism Spectrum Disorder: Assessment of Speech, Language, and Communication Disorders in
      • Autism Spectrum Disorder: School Consultation
      • Autism Spectrum Rating Scales
      • Bayley Scales of Infant and Toddler Development
      • Behavior Checklists
      • Child Behavior Checklist
      • Chromosomal Microarray
      • Cognitive Assessment System
      • Comprehensive Executive Functioning Inventory
      • Continuous Performance Tests
      • Developmental Interview
      • Diagnostic Reading Assessment
      • Differential Ability Scales
      • Dyslexia: Assessment
      • Executive Function Tests
      • Expressive Language Tests
      • Eye Tracking
      • Floortime
      • Functional Behavioral Analysis
      • Genetic Counseling
      • Giftedness
      • Infant Visual Attention and Response to Novelty
      • Intellectual Disability, Assessment of Adults With
      • Intellectual Disability, Assessment of Children With
      • Intelligence: IQ Scores
      • Intelligence-Achievement Discrepancy
      • Labeling, Pros and Cons of
      • Magnetic Resonance Imaging
      • Mental Status Examination
      • Mullen Scales of Early Learning
      • Neuroimaging Methods
      • Neurological Examination
      • Neuropsychological Assessment
      • Newborn Screening
      • Noninvasive Brain Stimulation
      • Nonverbal Assessment of Intelligence
      • Processing Speed
      • Psychological Testing
      • Receptive Language Tests
      • Stanford-Binet Intelligence Scales
      • Structured Interviews
      • Testing for Prenatal Birth Defects
      • Vineland Adaptive Behavior Scales
      • Wechsler Adult Intelligence Scale
      • Wechsler Individual Achievement Test
      • Wechsler Intelligence Scale for Children
      • Wechsler Preschool and Primary Scale of Intelligence
      • Whole Genome Sequencing
      • Woodcock-Johnson Tests of Achievement
      • Woodcock-Johnson Tests of Cognitive Abilities
      • Written Expression, Tests of
    • Comorbidity and Associated Features
      • Aggression
      • Alcohol Abuse in Individuals With Intellectual and Developmental Disabilities
      • Allergies
      • Aphasia
      • Apraxia
      • Blindness
      • Cleft Lip and Cleft Palate
      • Deafness and Hearing Loss
      • Depressogenic Conditions
      • Diagnostic Overshadowing
      • Dual Diagnosis
      • Echolalia
      • Empathy
      • Encopresis
      • Enuresis
      • Executive Functioning
      • Fine Motor Delays
      • Gross Motor Delay
      • Hyperkinesis
      • Hypertonia and Hypotonia
      • Infantile Automatisms
      • Joint Attention
      • Mania
      • Munchausen by Proxy
      • Nonepileptic Stress Induced Seizures
      • Obesity
      • Obsessions and Compulsions
      • Otitis Media
      • Panic Attacks
      • Peer Rejection
      • Perseveration
      • Phobias
      • Pica
      • Pragmatics
      • Psychosis
      • Regression
      • Repetitive Behaviors and Interests
      • Resilience, Learning Disorders and
      • Seizures
      • Self-Injury
      • Self-Stimulatory Behaviors
      • Sensory Integration Issues
      • Sexual Abuse
      • Sexual Exploitation
      • Sexualized Behavior
      • Siblings of Individuals With Developmental Disorders
      • Sleep Disorders
      • Social Anxiety
      • Social Skills Deficits
      • Stereotypy
      • Stuttering
      • Substance Use
      • Suicide
      • Trauma
    • Development
      • Adolescence
      • Cognitive Development
      • Developmental Milestones
      • Early Childhood Development
      • Elementary School-Aged Children With Intellectual and Developmental Disabilities
      • Emotional Development
      • Fine Motor Development
      • Gross Motor Development
      • Infancy
      • Intelligence: Environmental Factors
      • Memory
      • Metacognition
      • Moral Development
      • Nature and Nurture
      • Neurobiology of Developmental Disabilities
      • Phenotype
      • Piaget’s Theory of Cognitive Development
      • Preschool Intellectual and Developmental Disorders
      • Readiness Skills
      • Self-Regulation
      • Social Cognition
      • Social Skills
      • Speech and Language Development
      • Temperament
      • Theory of Mind
      • Transitional Age Youth
      • Visual Motor Coordination
      • Visual Spatial Skills
    • Developmental and Intellectual Disorders
      • 16p11.2 Deletion and Duplication Syndromes
      • 18p Deletion Syndrome
      • 22q11.2 Deletion Syndrome
      • Acute Disseminated Encephalomyelitis
      • Adrenoleukodystrophy and Other Leukodystrophies
      • Agenesis of the Corpus Callosum
      • Alice in Wonderland Syndrome
      • Asperger Syndrome
      • Autism Spectrum Disorder
      • Cerebral Palsy
      • Childhood Disintegrative Disorder
      • Chromosome 15 Disorders
      • Cornelia de Lange Syndrome
      • Cri-du-Chat Syndrome
      • Dandy-Walker Syndrome
      • Down Syndrome
      • Epilepsy
      • Failure to Thrive
      • Fetal Alcohol Spectrum Disorders
      • Fragile X Syndrome
      • Global Developmental Delay
      • Intellectual Disability
      • Intellectual Disability, Abuse and
      • Intellectual Disability: Comorbidity
      • Intellectual Disability: Development and Outcome
      • Intellectual Disability: Mild
      • Intellectual Disability: Moderate
      • Intellectual Disability: Severe and Profound
      • Klinefelter Syndrome
      • Landau-Kleffner Syndrome
      • Learning Disorders: Relationship to Other Neurodevelopmental Disorders
      • Mitochondrial Disorders
      • Multiple Sclerosis
      • Muscular Dystrophies
      • Neonatal Abstinence Syndrome
      • Neurofibromatosis
      • Noonan Syndrome
      • Patau Syndrome
      • Pitt-Hopkins Syndrome
      • Prader–Willi Syndrome
      • Rett Syndrome
      • Rubinstein-Taybi Syndrome
      • Shaken Baby Syndrome
      • Smith-Magenis Syndrome
      • Spina Bifida
      • Stroke, Prenatal
      • Strokes, Perinatal and Pediatric
      • Sturge-Weber Syndrome
      • Subacute Sclerosing Panencephalitis
      • Triple X Syndrome
      • Trisomy
      • Tuberous Sclerosis
      • Turner Syndrome
      • Williams Syndrome
      • Wilson’s Disease
    • Education
      • 504 Plan
      • Accommodations
      • Adult Literacy
      • American Sign Language
      • Autism Spectrum Disorder: School Consultation
      • Camp Shriver
      • Case Management and Care Coordination
      • Early Childhood Education for Students With Developmental Disabilities
      • Early Intervention
      • Early Start Denver Model
      • Educational Advocacy
      • Elementary Education for Students With Developmental Disabilities
      • Employment for Individuals With Autism Spectrum Disorder
      • Employment for Individuals With Intellectual Disabilities
      • Families as Partners in Educational Decision Making
      • Free Appropriate Public Education
      • Future Research Directions in Developmental Disabilities
      • Head Start Programs
      • Homeschooling
      • Homework
      • Inclusion
      • Individualized Education Program
      • Individualized Family Service Plan
      • Individuals with Disabilities Education Act
      • Infant Stimulation Programs
      • Intelligence: IQ Scores
      • Job Coaching
      • Learning Disorders: Relationship to Other Neurodevelopmental Disorders
      • Least Restrictive Environment, Current Practices in
      • Life Skills Coaching
      • Mainstreaming, Current Practices in
      • Mentoring
      • Multidisciplinary Approaches to Teaching Students With Developmental Disabilities
      • Online Learning
      • Peer Tutoring
      • Physical Activity and Children and Youth With Intellectual and Developmental Disabilities
      • Portage Project
      • Positive Behavior Support and Developmental Disabilities
      • Postsecondary Education for Students With Disabilities
      • Program Evaluation
      • Readiness Skills
      • Reading Programs: Teaching Students With Intellectual Disabilities and Moderate-to-Severe Reading Disabilities
      • Regular Education Initiative
      • Secondary Education for Students With Developmental Disabilities
      • Section 504 and the Education of Children With Disabilities
      • Self-Contained Classrooms
      • Social Skills Groups for Individuals With Autism Spectrum Disorders
      • Special Education
      • Support Groups for Adults With Intellectual and Developmental Disabilities
      • Support Groups for Families of Children With Developmental Disorders
      • Supportive Employment
      • Technology for Individuals With Intellectual and Developmental Disabilities
      • Technology-Enhanced Learning
      • Universal Design for Learning
    • Gender, Culture, and Ethnicity
      • Larry P. v. Riles
      • Bilingualism
      • Cultural Differences in Discipline
      • Cultural Norms
      • Culturally Sensitive Assessment
      • Famous People With Intellectual and Developmental Disabilities
      • Gender Differences
      • Intelligence Tests, Effect of Culture and Ethnicity on
      • International Perspectives on Developmental Disabilities
      • Maltreatment of Persons With Intellectual Disabilities
      • Media Portrayals of Individuals With Developmental Disabilities
      • Parenting Style
      • People-First Language
      • Race and Ethnicity
      • Stigma
      • Student–Teacher Relationships
    • Health, Wellness, and Resiliency
      • Activities of Daily Living
      • Allergies
      • Bullying
      • Commercial Sexual Exploitation of Children
      • Dating and Close Relationships
      • Emotional Abuse
      • Employment for Individuals With Autism Spectrum Disorder
      • Employment for Individuals With Intellectual Disabilities
      • End-of-Life Care
      • Estate Planning
      • Family Impact in Adulthood
      • Friendships
      • Funding Services for Adults With Developmental Disabilities and Autism Spectrum Disorder
      • Giftedness
      • Health Promotion
      • Health-Related Disorders
      • Identity Development
      • Intellectual Disability: Prevention
      • Learned Helplessness
      • Life Skills
      • Lifespan Developmental Theories
      • Long-Term Supports and Services
      • Parental Adaptation
      • Parental Stress
      • Partnering With Refugees With Intellectual and Developmental Disabilities and Their Families
      • Peer Acceptance
      • Physical Abuse
      • Physical Activity and Children and Youth With Intellectual and Developmental Disabilities
      • Prevention of Intellectual and Developmental Disabilities
      • Protective Factors
      • Quality of Life
      • Resilience, Characteristics of
      • Respite Care
      • Self-Esteem
      • Sexual Awareness and Knowledge
      • Sexual Development, Physical
      • Sexuality in Autism Spectrum Disorder
      • Sexuality in Children and Adolescents With Developmental Disorders
      • Sexuality in Intellectual Disabilities
      • Social Support
      • Special Olympics
      • Splinter Skills and Cognitive Strengths in Autism
      • Sports
      • Stress and Coping
      • Supported Living
      • TEACCH
      • Transitional Age Youth
      • Vaccinations and Autism
    • Historical Views of Intelligence and Development
      • Diagnostic and Statistical Manual of Mental Disorders
      • International Classification of Diseases, 10th Revision
      • International Classification of Diseases, History of
      • Autism and Autism Spectrum Disorders, History of
      • Civil Rights of Institutionalized Persons Act
      • Crystallized Intelligence
      • Deinstitutionalization
      • Disability Rights Movement
      • Education for All Handicapped Children Act
      • Epidemiology, Historical Changes in
      • Eugenics Movement
      • Fluid Intelligence
      • Flynn Effect
      • Head Start, History of
      • Intellectual Disability, History of
      • Intelligence, Historical Views of
      • Least Restrictive Environment, History of
      • Mainstreaming, History of
      • Special Education, History of
    • Learning, Psychological, and Behavioral Disorders
      • Adjustment Disorders
      • Attention-Deficit/Hyperactivity Disorder
      • Bipolar Disorder
      • Conduct Disorder
      • Depression
      • Developmental Coordination Disorder
      • Developmental Dyscalculia
      • Disorders of Elimination
      • Disruptive Behavior Disorders
      • Disruptive Mood Dysregulation Disorder
      • Dysgraphia
      • Dyslexia
      • Dyslexia: Treatment
      • Eating Disorders
      • Feeding Disorders of Infancy or Childhood
      • Generalized Anxiety Disorder
      • Language Disorders
      • Learning Disorders
      • Nonverbal Learning Disability
      • Obsessive-Compulsive Disorder
      • Oppositional Defiant Disorder
      • Panic Attacks
      • Panic Disorder
      • Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infections
      • Posttraumatic and Acute Stress Disorders
      • Rumination Syndrome
      • Schizophrenia, Adult Onset
      • Schizophrenia, Early Onset
      • School Refusal
      • Selective Mutism
      • Separation Anxiety Disorder
      • Social (Pragmatic) Communication Disorder
      • Social Anxiety
      • Specific Phobia
      • Speech Sound Disorder
      • Tic Disorders
      • Tourette’s Disorder
    • Public Policy Issues
      • Larry P. v. Riles
      • Americans with Disabilities Act
      • Arc of the United States, The
      • Article 12 of the Convention on the Rights of Persons with Disabilities
      • Camp Shriver
      • Classroom Aides
      • Conservatorship
      • Council for Exceptional Children
      • Death Penalty and Intellectual Disability
      • Decision-Making Capacity
      • Dispute Resolution
      • Down Syndrome: Cognitive, Emotional, and Behavioral Presentation
      • Down Syndrome: Medical Concerns and Comorbid Disorders
      • Education for All Handicapped Children Act
      • Ethical Issues in Education
      • Ethical Issues in Research, Current Standards in
      • Ethical Issues in Research, History of
      • Ethical Issues in Treatment
      • Federal Funding for Children With Intellectual and Developmental Disabilities
      • Financial Abuse
      • Free Appropriate Public Education
      • Funding Services for Adults With Developmental Disabilities and Autism Spectrum Disorder
      • Guardianship
      • Inclusion
      • Labeling, Impact of
      • Labeling, Pros and Cons of
      • Section 504 and the Education of Children With Disabilities
      • Special Education Law: U.S. Supreme Court Cases
    • Research
      • Consent in Research and Treatment
      • Disability Research Methodology
      • Epidemiology
      • Familial Aggregation Studies
      • Flynn Effect
      • Future Research Directions in Developmental Disabilities
      • Genetic Research
      • Longitudinal Research
      • Multiple Baseline Design
      • Naturalistic Observation
      • Randomized Controlled Trials
      • Single Case Research Design
      • Treatment Intervention
    • Theories and Causes: Biological Perspectives
      • Acquired Pediatric Brain Damage
      • Anoxia
      • Autism Spectrum Disorder, Biology of
      • Basal Ganglia
      • Birth Defects
      • Brain Plasticity
      • Brain Tumors, Pediatric
      • Brainstem
      • Central Nervous System
      • Cerebellum
      • Cerebral Cortex
      • Cingulate Cortex
      • Cognitive Neuroscience of Intelligence
      • Concussion
      • Corpus Callosum
      • Cross Disorder Genetic Risk
      • Developmental Psychopathology
      • Down Syndrome: Medical Concerns and Comorbid Disorders
      • Encephalitis
      • Endophenotypes
      • Failure to Thrive
      • Frontal Lobes
      • Genetics of Intellectual Development
      • Hemispheric Asymmetries
      • Herpes Simplex
      • Hormones
      • Human Genome Project
      • Hydrocephalus
      • Iatrogenic Effects
      • Intellectual Disability, Biology of
      • Lead Poisoning
      • Learning Disorders, Biology of
      • Limbic System
      • Maternal Substance Abuse
      • Media Use by Individuals With Intellectual and Developmental Disabilities
      • Meningitis
      • Microcephaly
      • Monogenic Disorders
      • Mosaicism
      • Myelination and Connectivity
      • Neural Plasticity
      • Neuroimaging Methods
      • Neurotransmitters
      • Nutrition in Childhood and Adolescence
      • Nutrition, Prenatal
      • Nutrition: Importance in First Years of Life
      • Polygenic Risk
      • Postnatal Risk Factors
      • Prenatal Risk Factors
      • Preterm Birth
      • Rubella
      • Temporal Lobe
      • Teratogens
    • Theories and Causes: Psychological and Sociocultural Perspectives
      • Attachment Theory
      • Autism, Rising Prevalence of: Epidemiology
      • Autism, Rising Prevalence of: Theories
      • Disability Discrimination: U.S. Supreme Court Cases
      • Down Syndrome: Cognitive, Emotional, and Behavioral Presentation
      • Ecological Systems Theory
      • Environmental Considerations in Social Participation of Children With Developmental Disabilities
      • Environmental Risk Factors
      • Erikson’s Theory of Psychosocial Development
      • Gardner’s Theory of Multiple Intelligences
      • Intelligence, Theories of
      • Intelligence: Environmental Factors
      • Piaget’s Theory of Cognitive Development
      • Vulnerability Stress Model
      • Vygotsky’s Zone of Proximal Development
    • Therapies and Interventions
      • Access to Treatment for Individuals With Intellectual and Developmental Disabilities
      • Accessible Design
      • Adaptive Functioning
      • Anchored Instruction
      • Applied Behavior Analysis
      • Art Therapy
      • Assistive Technology
      • Attention-Deficit/Hyperactivity Disorder: Potential Misuse of Stimulant Medications
      • Augmentative and Alternative Communication
      • Behavior Modification
      • Behavior Therapy
      • Biofeedback
      • Braille, Use in Individuals With Visual Impairment
      • Classroom Aides
      • Cognitive Behavioral Therapy
      • Cognitive Rehabilitation Training
      • Community-Based Interventions
      • Consent in Research and Treatment
      • Dementia
      • Dementia and Aging in Down Syndrome
      • Discrete Trial Training
      • Early Intervention
      • Early Start Denver Model
      • Executive Function Coaching
      • Extinction
      • Family-Based Interventions
      • Flooding
      • Floortime
      • Functional Inclusion
      • Intellectual Disability: Historical Changes in Terminology
      • Male Brain Theory of Autism
      • Mentoring
      • Metacognitive Training
      • Mindfulness-Based Treatments
      • Mood Stabilizers
      • Music Therapy
      • Nutritional Therapies for Children With Developmental Disabilities
      • Occupational Therapy
      • Parent–Child Interaction Therapy
      • Personalized Supports
      • Phonics-Based Interventions
      • Physical Therapy
      • Picture Exchange Communication System
      • Pivotal Response Therapy
      • Portage Project
      • Positive Parenting of Children With Intellectual and Developmental Disabilities
      • Prenatal Care
      • Probiotics
      • Psychopharmacological Interventions
      • Relationship Development Intervention
      • Social Inclusion
      • Speech and Language Pathologists
      • Stimulant Medications
      • Systematic Desensitization
      • Technology for Individuals With Intellectual and Developmental Disabilities
      • Treatment Planning
      • UCLA Young Autism Project
    • A
    • B
    • C
    • D
    • E
    • F
    • G
    • H
    • I
    • J
    • K
    • L
    • M
    • N
    • O
    • P
    • Q
    • R
    • S
    • T
    • U
    • V
    • W
    • X
    • Y
    • Z

    Entries by Letter: Entries Per Page:

  • Entries by Letter: 174030
    • Loading…

About the author

Leave a Reply

Your email address will not be published. Required fields are marked *