Other Names for this Disease
- Klinefelter's syndrome
- XXY syndrome
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hypogonadism (decreased testosterone production), small testes, enlarged breast tissue (gynecomastia), tall stature, and/or infertility. KS is not inherited, but usually occurs as a random event during the formation of reproductive cells (eggs and sperm). Treatment is based on the signs and symptoms present in each person.Klinefelter syndrome (KS) is a condition that occurs in males when they have an extra X chromosome. Some males with KS have no obvious signs or symptoms while others may have varying degrees of cognitive, social, behavioral, and learning difficulties. Adults with Klinefelter syndrome may also experience primary
Last updated: 10/13/2015
- 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.
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) provides information related to the health of children, adults, and families. Click on the link to view information on this topic.
- Genetics Home Reference (GHR) contains information on Klinefelter syndrome. This website is maintained by the National Library of Medicine.
- MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
- The National Human Genome Research Institute's (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
- The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
- Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
- MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
- The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
- Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Klinefelter syndrome. Click on the link to view a sample search on this topic.