XLMR syndrome characterized by multiple respiratory infections, hypertelorism, severe CNS deterioration and early death localizes to distal Xq28

We report on a family with severe X-linked mental retardation (XLMR) and pr ogressive, severe central nervous system deterioration. Three of the five a ffected males died of secondary complications before the age of 10 years an d none have survived past the age of 10. These complications included swall owing dysfunction and gastroesophageal reflux with secondary recurrent resp iratory infections. In addition, hypotonia and a mild myopathy were also pr esent. All had a characteristic facies, including downslanting palpebral fi ssures, hypertelorism, and a short nose with a low nasal bridge. The two ol der boys showed cerebral atrophy by CT. No metabolic abnormalities were ide ntified, Three obligate carriers had an IQ less than 80. The causal gene has been localized distal to DXS8103 in Xq28, a region span ning 5cM, No other XLMR disorder with these manifestations have been locali zed to this region and this appears to be a new disorder. Am. J. Med. Genet . 85:243-248, 1999. (C) 1999 Wiley-Liss, Inc.