Abstract
X-linked mental retardation (XLMR) is a common cause of inherited intellectual disability with an estimated prevalence of ∼1/1000 males. Most XLMR conditions are inherited as X-linked recessive traits, although female carriers may manifest usually milder symptoms. We have listed 215 XLMR conditions, subdivided according to their clinical presentation: 149 with specific clinical findings, including 98 syndromes and 51 neuromuscular conditions, and 66 nonspecific (MRX) forms. We also present a map of the 82 XLMR genes cloned to date (November 2007) and a map of the 97 conditions that have been positioned by linkage analysis or cytogenetic breakpoints. We briefly consider the molecular function of known XLMR proteins and discuss the possible strategies to identify the remaining XLMR genes. Final remarks are made on the natural history of XLMR conditions and on diagnostic issues.
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Acknowledgements
This work has been supported in part by TELETHON grant (GGP06224), PRIN 2005 grant (no.2005060575) and a Conquer Fragile X Foundation grant to GN.; and by Grant HD26202 from NICHD and by the South Carolina Department of Disabilities and Special Needs to CES. This paper is dedicated to the memory of Libor Kozák (1960–2007) and of Ethan Francis Schwartz (1996–1998).
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Chiurazzi, P., Schwartz, C., Gecz, J. et al. XLMR genes: update 2007. Eur J Hum Genet 16, 422–434 (2008). https://doi.org/10.1038/sj.ejhg.5201994
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DOI: https://doi.org/10.1038/sj.ejhg.5201994
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