- Klinefelter's syndrome
- XXY syndrome
Your QuestionKlinefelter syndrome can be caused by nondisjunction. What increases the risk of males or females to have nondisjunction during meiosis? What research is currently underway for Klinefelter syndrome?
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In some cases, the two X chromosomes or the X chromosome and Y chromosome fail to pair and fail to exchange genetic material. Occasionally, this results in their moving independently to the same cell, producing either an egg with two Xs, or a sperm having both an X and a Y chromosome. When a sperm having both an X and a Y chromosome fertilizes an egg having a single X chromosome, or a normal Y- bearing sperm fertilizes an egg having two X chromosomes, an XXY male is conceived.
You can also contact the Patient Recruitment and Public Liaison (PRPL) Office at the National Institutes of Health (NIH). We recommend calling the toll-free number listed below to speak with a specialist, who can help you determine if you are eligible for any clinical trials. If you are located outside the United States, and would like to be contacted via telephone, you will need to provide your telephone number in full, including area code and international dialing prefix.
Patient Recruitment and Public Liaison Office
NIH Clinical Center
Bethesda, Maryland 20892-2655
Web site: http://clinicalcenter.nih.gov/
You can find helpful general information on clinical trials at the following ClinicalTrials.gov Web page.
A tutorial about clinical trials that can also help answer your questions can be found at the following link from the National Library of Medicine:
- Klinefelter syndrome. Eunice Kennedy Shriver National Institute of Child Health and Human Development. November 2013; http://www.nichd.nih.gov/health/topics/klinefelter/Pages/default.aspx.
- Klinefelter syndrome. Genetics Home Reference. January 2013; http://ghr.nlm.nih.gov/condition=klinefeltersyndrome.
- Kirmse B. Klinefelter syndrome. MedlinePlus. November 2014; http://www.nlm.nih.gov/medlineplus/ency/article/000382.htm.
- Nondisjunction. OMIM. May 2006; http://www.omim.org/entry/158250.