Klinefelter's syndrome

Definition

Klinefelter syndrome is a chromosome disorder in males. People with this condition are born with at least one extra X chromosome.

Description

Klinefelter syndrome is a condition where one or more extra X-chromosomes are present in a male. Boys with this condition appear normal at birth. They enter puberty normally, but by mid puberty have low levels of testosterone causing small testicles and the inability to make sperm. Affected males may also have learning disabilities and behavior problems such as shyness and immaturity and an increased risk for certain other health problems.

Klinefelter syndrome is one of the most common chromosomal abnormalities. About 1 in every 500 to 800 males is born with this disorder. Approximately 3% of the infertile male population have Klinefelter syndrome.

— Carin Lea Beltz, M.S.

(medicine) A complex of symptoms associated with hypogonadism in males as an accompaniment of an anomaly of the sex chromosomes; somatic cells are found to have a Y chromosome and more than one X chromosome.

A syndrome of gonadal defects, appearing in males with an extra X chromosome in at least one cell line. Characteristics are small, firm testes, long legs, gynecomastia, poor social adaptation, subnormal intelligence, chronic pulmonary disease, and varicose veins.

Definition

Klinefelter syndrome is a chromosome disorder in males that results in hypogonadism (small penis and small firm testicles). People with this condition are born with at least one extra X chromosome.

Description

Klinefelter syndrome is a condition where one or more extra X-chromosomes are present in a male. Boys with this condition appear normal at birth, but the defect becomes apparent in puberty when secondary sexual characteristics fail to develop, or develop later. By mid-puberty, boys with Klinefelter syndrome have low levels of testosterone, resulting in small testicles and the inability to make sperm. Affected males may also have learning disabilities and behavior problems such as shyness and immaturity and at an increased risk for certain other health problems such as pulmonary disease, varicose veins, breast cancer, extragonadal germ cell tumor (a rare tumor), and osteoporosis. Some mild cases may be undetected, with no abnormalities present except infertility.

Demographics

Klinefelter syndrome is one of the most common chromosomal abnormalities. About 1 in every 500 to 800 males is born with this disorder. Approximately 3% of the infertile male population have Klinefelter syndrome.

Causes and Symptoms

Normally, a person has a total of 46 chromosomes in each cell, two of which are responsible for determining that individual's sex. These two sex chromosomes are called X and Y. The combination of these two types of chromosomes determines the sex of a child. Females have two X chromosomes (the XX combination); males have one X and one Y chromosome (the XY combination).

In Klinefelter syndrome, a problem very early in fetal development results in an abnormal number of chromosomes. Most commonly, a male with Klinefelter syndrome will be born with 47 chromosomes in each cell, rather than the normal number of 46. The extra chromosome is an X chromosome. This means that rather than having the normal XY combination, the male has an XXY combination. Because people with Klinefelter syndrome have a Y chromosome, they are all male.

Approximately 1/3 of all males with Klinefelter syndrome have other chromosome changes involving an extra X chromosome. Mosaic Klinefelter syndrome occurs when some of the cells in the body have an extra X chromosome and the other have normal male chromosomes. These males can have the same or milder symptoms than those with non-mosaic Klinefelter syndrome. Males with more than one additional extra X chromosome, such as 48, XXXY, are usually more severely affected than males with 47,XXY.

Klinefelter syndrome is not considered an inherited condition. The risk of Klinefelter syndrome reoccurring in another pregnancy for a woman who had a son with Klinefelter syndrome is not increased above the risk of the general population.

The symptoms of Klinefelter syndrome are variable; not every affected person will have all of the features of the condition. Males with Klinefelter syndrome appear normal at birth and have normal male genitalia. From childhood, males with Klinefelter syndrome are taller than average with long limbs. Approximately 20–50% have a mild intention tremor, an uncontrolled shaking. Many males with Klinefelter syndrome have poor upper body strength and can be clumsy. Klinefelter syndrome does not cause homosexuality. Approximately 1/3 of males with Klinefelter syndrome have breast growth, some requiring breast reduction surgery.

Most boys enter puberty normally, though some can be delayed. The Leydig cells in the testicles usually produce testosterone. With Klinefelter syndrome, the Leydig cells fail to work properly causing the testosterone production to slow. By mid-puberty, testosterone production is decreased to approximately half of normal. This can lead to decreased facial and pubic hair growth. The decreased testosterone also causes an increase in two other hormones, follicle stimulating hormone (FSH) and luteinizing hormone (LH). Normally, FSH and LH help the immature sperm cells grown and develop. In Klinefelter syndrome, there are few or no sperm cells. The increased amount of FSH and LH cause hyalinization and fibrosis, the growth of excess fibrous tissue, in the seminiferous tubules, where the sperm are normally located. As a result, the testicles appear smaller and firmer than normal. With rare exception, men with Klinefelter syndrome are infertile because they can not make sperm.

While it was once believed that all boys with Klinefelter syndrome were mentally retarded, doctors now know that the disorder can exist without retardation. However, children with Klinefelter syndrome frequently have difficulty with language, including learning to speak, read, and write. Approximately 50% of males with Klinefelter syndrome are dyslexic. They may also have attention deficient hyperactivity disorder.

Some people with Klinefelter syndrome have difficulty with social skills and tend to be more shy, anxious, or immature than their peers. They can also have poor judgement and do not handle stressful situations well. As a result, they often do not feel comfortable in large social gatherings. Some people with Klinefelter syndrome can also have anxiety, nervousness and/or depression.

Taurodontism, an enlargement of the pulp of the teeth with surface thinning, is very common in Klinefelter syndrome and can be diagnosed with dental x rays.

The greater the number of X chromosomes present, the greater the disability. Boys with several extra X chromosomes have distinctive facial features, more severe retardation, deformities of bony structures, and even more disordered development of male features.

When to Call the Doctor

Parents should call a doctor if their son fails to develop secondary sexual characteristics at puberty.

Diagnosis

During a physical examination, a doctor will look for a simian crease (a single crease in the palm). A rectal exam may show an enlarged prostate. A single testicle may be present in the scrotum, indicating a probable undescended testicle. A semen examination will show low sperm count, while other tests will show decreased serum testosterone levels, increased levels of serum luteining and serum follicle stimulating hormones and increased serum estradiol levels (a type of estrogen).

Diagnosis of Klinefelter syndrome is confirmed by examining chromosomes for evidence of more than one X chromosome present in a male. This can be done in pregnancy with prenatal testing such as chorionic villus sampling or amniocentesis. Chorionic villus sampling is a procedure done early in pregnancy (approximately 10–12 weeks) to obtain a small sample of the placenta for testing. An amniocentesis is done further along in pregnancy (from approximately 16–18 weeks) to obtain a sample of fluid surrounding the baby for testing. Both procedures have a risk of miscarriage. Usually these procedures are done for a reason other than diagnosing Klinefelter syndrome. For example, a prenatal diagnostic procedure may be done on an older woman to determine if her baby has Down syndrome. If the diagnosis of Klinefelter syndrome is suspected in a young boy or adult male, chromosome testing can also be on a small blood or skin sample after birth.

Treatment

There is no treatment available to change chromosomal makeup. Children with Klinefelter syndrome may benefit from a speech therapist for speech problems or other educational intervention for learning disabilities. Testosterone injections started around the time of puberty and continued for life may help to produce more normal development, including more muscle mass, hair growth and increased sex drive. Testosterone supplementation will not increase testicular size, decrease breast growth or correct infertility.

Prognosis

While many men with Klinefelter syndrome live normal lives, nearly 100 percent of these men will be sterile (unable to produce a child). However, a few men with Klinefelter syndrome have been reported who have fathered a child through the use of assisted fertility services. Males with Klinefelter syndrome have an increased risk of several conditions such as osteoporosis, pulmonary disease, varicose veins, autoimmune disorders such as lupus and arthritis, diabetes, breast cancer and extragonadal germ cell tumor (a rare tumor).

Prevention

Klinefelter syndrome usually is not inherited but occurs during fetal development, so there is no means of preventing the disease. However, one risk factor for this condition is the mother giving birth at an older age; therefore, genetic counseling and testing is recommended.

Parental Concerns

Families may wish to seek counseling regarding the effects of the syndrome on relationships within the family. Many people respond with guilt, fear, or blame when a genetic disorder is diagnosed in the family, or they may overprotect the affected member. Support groups are often good sources of information about Klinefelter syndrome; they can offer helpful suggestions about living with it as well as emotional support.

Resources

Books

Bock, R. Understanding Klinefelter's Syndrome: A Guide for XXY Males and Their Families. Bethesda, MD: National Institutes of Health,1993.

Icon Health Publications. Klinefelter's Syndrome: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References. San Diego, CA:Icon Health Publications, 2004.

Icon Health Publications. The Official Parent's Sourcebook on Klinefelter Syndrome. San Diego, CA:Icon Health Publications, 2002.

Probasco, Teri, and Gretchen A. Gibbs. Klinefelter Syndrome. Richmond, IN: Prinit Press, 1999.

Organizations

American Association for Klinefelter Syndrome Information and Support. 2945 West Farwell Avenue, Chicago, IL 60645-2925. (773) 761-5298, (800) 466-5747.

Klinefelter's Organisation. 234 Turton Road, Bolton, BL2 3EE, United Kingdom.

Klinefelter Syndrome and Associates, Inc. PO Box 119, Roseville, CA 95678-0119. (916) 773-2999 or (888) 999-9428. Fax: (916) 773-1449. .

Web Sites

Klinefelter Syndrome Support Group Home Page.

[Article by: Judith Sims, MS Carin Lea Beltz, MS]

For more information on Klinefelter syndrome, visit Britannica.com.

A condition in humans characterized by the presence of small testes, with fibrosis and hyalinization of the seminiferous tubules, impairment of function and clumping of Leydig cells, and an increase in urinary gonadotropins, associated with an abnormality of the sex chromosomes. It is associated typically with an XXY chromosome complement. A similar condition is seen in male tortoiseshell and white cats, and has been recorded rarely in stallions, bulls, rams and dogs.

Not to be confused with XYY syndrome.

"XXY" redirects here. For the Lucía Puenzo film, see XXY (film).

Klinefelter's syndrome
Classification and external resources
47,XXY
ICD-10	Q98.0-Q98.4
ICD-9	758.7
eMedicine	ped/1252
MeSH	D007713

Klinefelter's syndrome, 47, XXY or XXY syndrome is a condition in which males have an extra X sex chromosome. While females have an XX chromosomal makeup, and males an XY, affected individuals have at least two X chromosomes and at least one Y chromosome.^[1] Klinefelter's syndrome is the most common sex chromosome disorder^[2] and the second most common condition caused by the presence of extra chromosomes. The condition exists in roughly 1 out of every 1000 males. One in every 500 males have an extra x chromosome but do not have the syndrome.^[3]

The principal effects are development of small testicles and reduced fertility. A variety of other physical and behavioral differences and problems are common, though severity varies and many boys and men with the condition have few detectable symptoms. Named after Dr. Harry Klinefelter, an endocrinologist at Massachusetts General Hospital, Boston, Massachusetts, who first described it in 1942^[4]. Because of the extra chromosome, individuals with the condition are usually referred to as "XXY Males", or "47, XXY Males".^[5]

Contents 1 Signs and symptoms 2 Diagnosis 3 Cause 4 Treatment 5 Variations 6 See also 7 References 8 Further reading 9 External links

Signs and symptoms

Affected males are almost always effectively infertile although advanced reproductive assistance is sometimes possible.^[6] Some degree of language learning impairment may be present,^[7] and neuropsychological testing often reveals deficits in executive functions.^[8] In adults, possible characteristics vary widely and include little to no signs of affectedness, a lanky, youthful build and facial appearance, or a rounded body type with some degree of gynecomastia (increased breast tissue).^[9] Gynecomastia is present to some extent in about a third of affected individuals, a slightly higher percentage than in the XY population, but only about 10% of XXY males' gynecomastia is noticeable enough to require surgery.^[10]

The term "hypogonadism" in XXY symptoms is often misinterpreted to mean "small testicles" or "small penis". In fact, it means decreased testicular hormone/endocrine function. Because of this hypogonadism, patients will often have a low serum testosterone level but high serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels.^[11] Despite this misunderstanding of the term, however, it is true that XXY men often also have "microorchidism" (i.e. small testicles).^[11]

The more severe end of the spectrum of symptom expression is also associated with an increased risk of germ cell tumors, breast cancer,^[12] and osteoporosis,^[3] risks shared to varying degrees^[13] with females. Additionally, medical literature shows some individual case studies of Klinefelter's syndrome coexisting with other disorders, such as pulmonary disease, varicose veins, diabetes mellitus, and rheumatoid arthritis, but possible correlations between Klinefelter's and these other conditions are not well characterized or understood.^{[citation needed]}

In contrast to these potentially increased risks, it is currently thought that rare X-linked recessive conditions occur even less frequently in XXY males than in normal XY males, since these conditions are transmitted by genes on the X chromosome, and people with two X chromosomes are typically only carriers rather than affected by these X-linked recessive conditions.

There are many variances within the XXY population, just as in the most common 46,XY population. While it is possible to characterise 47,XXY males with certain body types, that in itself should not be the method of identification as to whether or not someone has 47,XXY. The only reliable method of identification is karyotype testing.

Diagnosis

A karyotype is used to confirm the diagnosis. In this procedure, a small blood sample is drawn. White blood cells are then separated from the sample, mixed with tissue culture medium, incubated, and checked for chromosomal abnormalities, such as an extra X chromosome.

Diagnosis can also be made prenatally via chorionic villus sampling or amniocentesis, tests in which fetal tissue is extracted and the fetal DNA is examined for genetic abnormalities. A 2002 literature review of elective abortion rates found that approximately 50% of pregnancies in the United States with a diagnosis of Klinefelter's syndrome were terminated.^[14]

Cause

The extra X chromosome is retained because of a nondisjunction event during meiosis (sex cell division). The XXY chromosome arrangement is one of the most common genetic variations from the XY karyotype, occurring in about 1 in 500 live male births.^[3]

In mammals with more than one X chromosome, the genes on all but one X chromosome are not expressed; this is known as X inactivation. This happens in XXY males as well as normal XX females.^[15] However, in XXY males, a few genes located in the pseudoautosomal regions of their X chromosomes, have corresponding genes on their Y chromosome and are capable of being expressed.^[16] These triploid genes in XXY males may be responsible for symptoms associated with Klinefelter's syndrome.^{[citation needed]}

The first published report of a man with a 47,XXY karyotype was by Patricia A. Jacobs and Dr. J.A. Strong at Western General Hospital in Edinburgh, Scotland in 1959.^[17] This karyotype was found in a 24-year-old man who had signs of Klinefelter's syndrome. Dr. Jacobs described her discovery of this first reported human or mammalian chromosome aneuploidy in her 1981 William Allan Memorial Award address.^[18]

Treatment

The genetic variation is irreversible. Testosterone treatment is an option for some individuals who desire a more masculine appearance and identity. ^[19] Often individuals that have noticeable breast tissue or hypogonadism experience depression and/or social anxiety because they are outside of social norms. This is academically referred to as psychosocial morbidity.^[20] At least one study indicates that planned and timed support should be provided for young men with Klinefelter syndrome to ameliorate current poor psychosocial outcomes.^[20]

Variations

The 48, XXYY (male) syndrome occurs 1 in 18,000-40,000 births and has traditionally been considered to be a variation of Klinefelter's syndrome. XXYY tetrasomy is no longer generally considered a variation of KS,^{[citation needed]} although it has not yet been assigned an ICD-10 code.

Males with Klinefelter syndrome may have a mosaic 47,XXY/46,XY constitutional karyotype and varying degrees of spermatogenic failure. Mosaicism 47,XXY/46,XX with clinical features suggestive of Klinefelter syndrome is very rare. Thus far, only about 10 cases have been described in literature.^[21]

See also

• Aneuploidy
• Intersexuality
• Mosaic (genetics)
• True hermaphroditism
• XXYY syndrome

References

1. ^ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease. St. Louis, Mo: Elsevier Saunders. pp. 179. ISBN 0-7216-0187-1. 
2. ^ James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. p 549. ISBN 0721629210.
3. ^ ^{a b c} "Klinefelter Syndrome" (HTML). Health Information. National Institute of Health and Human Development. 2007-02-19. http://www.nichd.nih.gov/health/topics/klinefelter_syndrome.cfm. Retrieved on 2007-03-24.  and "Klinefelter syndrome" (HTML). Genetics Home Reference. National Library of Medicine. 2006. http://ghr.nlm.nih.gov/condition%3Dklinefeltersyndrome. Retrieved on 2007-03-24.  both provide statistical estimates.
4. ^ Klinefelter, HF Jr; Reifenstein, EC Jr; Albright (1942), "Syndrome characterized by gynecomastia, aspermatogenesis without a-Leydigism and increased excretion of follicle-stimulating hormone", J Clin Endocrinol Metab 2: 615–624 . Klinefelter, HF (1986), "Klinefelter's syndrome: historical background and development", South Med J 79 (45): 1089–1093, PMID 3529433  talks about the history of the development of the literature.
5. ^ Bock, Robert (August 1993). "Understanding Klinefelter Syndrome: A Guide for XXY Males and Their Families" (HTML). NIH Pub. No. 93-3202. Office of Research Reporting, NICHD. http://www.nichd.nih.gov/publications/pubs/klinefelter.cfm. Retrieved on 2007-04-07. 
6. ^ Denschlag, Dominik, MD; Clemens, Tempfer, MD; Kunze, Myriam, MD; Wolff, Gerhard, MD; Keck, Christoph, MD (October 2004), "Assisted reproductive techniques in patients with Klinefelter syndrome: A critical review", Fertility and Sterility 82 (4): 775–779, doi:10.1016/j.fertnstert.2003.09.085 
7. ^ Graham, JM Jr; Bashir, AS; Stark, RE; Silbert, A; Walzer, S (June 1988), "Oral and written language abilities of XXY boys: implications for anticipatory guidance", Pediatrics 81 (6): 795–806, PMID 3368277 
8. ^ Boone KB, Swerdloff RS, Miller BL, et al. (May 2001). "Neuropsychological profiles of adults with Klinefelter syndrome". J Int Neuropsychol Soc 7 (4): 446–56. doi:10.1017/S1355617701744013. PMID 11396547. 
9. ^ Abstract of Klinefelter, HF (1986), "Klinefelter's syndrome: historical background and development", South Med J 79 (9): 1089–1093, PMID 3529433  provides information on microorchidism (small testes), hypogonadism (infertility/sterility and androgen hormone function) and gynecomastia. Bock, Robert (August 1993). "Understanding Klinefelter Syndrome: A Guide for XXY Males and Their Families" (HTML). NIH Pub. No. 93-3202. Office of Research Reporting, NICHD. http://www.nichd.nih.gov/publications/pubs/klinefelter.cfm. Retrieved on 2007-03-28.  offers substantive information about body type and appearance until a more rigorous source is found/supplied.
10. ^ Bock, Robert (August 1993). "Understanding Klinefelter Syndrome: A Guide for XXY Males and Their Families, Adolescence section" (HTML). NIH Pub. No. 93-3202. Office of Research Reporting, NICHD. http://www.nichd.nih.gov/publications/pubs/klinefelter.cfm#xadol. Retrieved on 2007-03-29.  describes statistical occurrence of gynecomastia and surgical treatment.
11. ^ ^{a b} Leask, Kathryn (October 2005). "Klinefelter syndrome" (HTML). National Library for Health, Specialist Libraries, Clinical Genetics. National Library for Health. http://www.library.nhs.uk/genepool/ViewResource.aspx?resID=104897. Retrieved on 2007-04-07. 
12. ^ Hultborn, R; Hanson, C; Kopf, I; Verbiene, I; Warnhammar, E; Weimarck, A (1997 November-December), "Prevalence of Klinefelter's syndrome in male breast cancer patients", Anticancer Res. 17 (6D): 4293–4297, PMID 9494523 
13. ^ For instance, while Hultborn, R; Hanson, C; Kopf, I; Verbiene, I; Warnhammar, E; Weimarck, A (1997 November-December), "Prevalence of Klinefelter's syndrome in male breast cancer patients", Anticancer Res. 17 (6D): 4293–4297, PMID 9494523  shows a 50-fold increased risk of developing breast cancer versus normal males, study of the SEER Cancer Statistics Review (CSR) databases available at the National Cancer Institute reveal that female relative risk of breast cancer incidence compared to normal males is around a 100 to 200-fold increase, which indicates XXY males may not be as much at risk statistically as normal females are.
14. ^ Caroline Mansfield, Suellen Hopfer, Theresa M. Marteau (1999). "Termination rates after prenatal diagnosis of Down syndrome, spina bifida, anencephaly, and Turner and Klinefelter syndromes: a systematic literature review". Prenatal Diagnosis 19 (9): 808–812. doi:10.1002/(SICI)1097-0223(199909)19:9<808::AID-PD637>3.0.CO;2-B. http://www3.interscience.wiley.com/cgi-bin/abstract/65500197/ABSTRACT. PMID 10521836 This is similar to 90% results found by David W. Britt, Samantha T. Risinger, Virginia Miller, Mary K. Mans, Eric L. Krivchenia, Mark I. Evans (1999). "Determinants of parental decisions after the prenatal diagnosis of Down syndrome: Bringing in context". American Journal of Medical Genetics 93 (5): 410–416. doi:10.1002/1096-8628(20000828)93:5<410::AID-AJMG12>3.0.CO;2-F. PMID 10951466
15. ^ Chow J, Yen Z, Ziesche S, Brown C (2005). "Silencing of the mammalian X chromosome". Annu Rev Genomics Hum Genet 6: 69-92. PMID 16124854
16. ^ Blaschke RJ, Rappold G (2006). The pseudoautosomal regions, SHOX and disease. Curr Opin Genet Dev. Jun; 16:233-9. PMID 16650979
17. ^ Jacobs PA, Strong JA (January 31, 1959). "A case of human intersexuality having a possible XXY sex-determining mechanism". Nature 183 (4657): 302–3. doi:10.1038/183302a0. PMID 13632697. 
18. ^ Jacobs PA (September 1982). "The William Allan Memorial Award address: human population cytogenetics: the first twenty-five years". Am J Hum Genet 34 (5): 689–98. PMID 6751075. 
19. ^ Androgen deficiency and replacement therapy in men - http://www.mja.com.au/public/issues/180_10_170504/han10513_fm.html
20. ^ ^{a b} Simm PJ, Zacharin MR (April 2006). "The psychosocial impact of Klinefelter syndrome--a 10 year review". J. Pediatr. Endocrinol. Metab. 19 (4): 499–505. PMID 16759035. 
21. ^ Velissariou V, Christopoulou S, Karadimas C, Pihos I, Kanaka-Gantenbein C, Kapranos N, Kallipolitis G, Hatzaki A. (July - August 2006). "Rare XXY/XX mosaicism in a phenotypic male with Klinefelter syndrome: case report". Eur J Med Genet 49 (4): 331-337. PMID 16829354

Further reading

• Fales, C. L., Knowlton, B. J., Holyoak, K. J., Geschwind, D. H., Swerdloff, R. S., & Gonzalo, I. G. (2003). Working memory and relational reasoning in Klinefelter syndrome. Journal of the International Neuropsychology Society, 9, 839-847.

External links

• Klinefelter's syndrome at the Open Directory Project
• Site which discusses Causes, Symptoms and Treatments of Klinefelters Syndrome

v • d • e Pathology: chromosome abnormalities (Q90-Q99 · 758) Autosomal Trisomies Down syndrome (21) · Edwards syndrome (18) · Patau syndrome (13) Trisomy 9 · Warkany syndrome 2 (8) · Trisomy 22/Cat eye syndrome (22) · Trisomy 16 Monosomies/deletions Wolf-Hirschhorn syndrome (4) · Cri du chat/Chromosome 5q deletion syndrome (5) · Williams syndrome (7) · Jacobsen syndrome (11) · Miller-Dieker syndrome/Smith-Magenis syndrome (17) · 22q11.2 deletion syndrome (22) genomic imprinting (Angelman syndrome/Prader-Willi syndrome (15)) X/Y linked Monosomy Turner syndrome (XO) Trisomy/tetrasomy other karyotypes Klinefelter's syndrome (47,XXY) · 48,XXYY · 49,XXXXY Triple X syndrome (47,XXX) · 48,XXXX · 49,XXXXX 47,XYY Translocations Leukemia/lymphoma Lymphoid Burkitt's lymphoma t(8 MYC;14 IGH) · Follicular lymphoma t(14 IGH;18 BCL2) · Mantle cell lymphoma/Multiple myeloma t(11 CCND1:14 IGH) · Anaplastic large cell lymphoma t(2 ALK;5 NPM1) · Acute lymphoblastic leukemia Myeloid Philadelphia chromosome t(9 ABL; 22 BCR) · Acute myeloblastic leukemia with maturation t(8 RUNX1T1;21 RUNX1) · Acute promyelocytic leukemia t(15 PML,17 RARA) · Acute megakaryoblastic leukemia t(1 RBM15;22 MKL1) Other Ewing's sarcoma t(11 FLI1; 22 EWS) · Synovial sarcoma t(x SYT;18 SSX) · Dermatofibrosarcoma protuberans t(17 COL1A1;22 PDGFB) · Myxoid liposarcoma t(12 DDIT3; 16 FUS) · Desmoplastic small round cell tumor t(11 WT1; 22 EWS) · Alveolar rhabdomyosarcoma t(2 PAX3; 13 FOXO1) t (1 PAX7; 13 FOXO1) Gonadal dysgenesis Mixed gonadal dysgenesis · XX gonadal dysgenesis Other Fragile X syndrome · Uniparental disomy

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