Other Names for this Disease
- 48 XXXX
- 48 XXXX syndrome
- Tetra X
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X chromosome instead of two. Females 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, but can include mild to moderate speech and learning difficulties; developmental delay; distinctive facial features; dental abnormalities; hypotonia and joint laxity; radioulnar synostosis; heart defects; hip dysplasia; and problems with ovarian function. An increased risk of childhood infections has also been reported. 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.Tetrasomy X is a chromosome disorder that only affects females and is caused by having four copies of the
Last updated: 2/19/2014
- Tetrasomy X. Unique. 2005; http://www.rarechromo.org/information/Chromosome_X/Tetrasomy_X%20FTNW.pdf. Accessed 9/11/2012.
- N Ayari, A Berge, Susan Howell, and Nicole Tartaglia. Tetrasomy X. Orphanet. January, 2010; http://www.orpha.net/consor/cgi-bin/Disease_Search.php?lng=EN&data_id=390. Accessed 2/19/2014.
- 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.
- 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 Tetrasomy X. Click on the link to view a sample search on this topic.