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Other Names for this Disease
- 48 XXXX
- 48 XXXX syndrome
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Tetrasomy X is a chromosome disorder that only affects females and is caused by having four copies of the X chromsome instead of two. Girls with tetrasomy X have a total of 48 chromosomes in their cells, so this condition is sometimes written as 48,XXXX. The signs and symptoms of tetrasomy X vary among people with this condition, but can include speech and learning difficulties that are usually mild to moderate. Girls with tetrasomy X tend to have more infections during childhood, and may also have an increased risk of ovarian problems later in life. Tetrasomy X is caused by a random error that occurs during the development of an egg cell, and is not caused by anything a mother does during her pregnancy.
Last updated: 9/11/2012
- Tetrasomy X. Unique. 2005; http://www.rarechromo.org/information/Chromosome_X/Tetrasomy_X%20FTNW.pdf. Accessed 9/11/2012.
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- Genetics Home Reference (GHR) contains information on Tetrasomy X. This website is maintained by the National Library of Medicine.
- Unique is a source of information and support to families and individuals affected by rare chromosome disorders. Click on the link to view information about tetrasomy X.