A GENE FOR NONSPECIFIC X-LINKED MENTAL-RETARDATION (MRX41) IS LOCATEDIN THE DISTAL SEGMENT OF XQ28

We report on a family in which non-syndromal mild to moderate mental r etardation segregates as an X-linked trait (MRX41), Two point linkage analysis demonstrated linkage between the disorder and marker DXS3 in Xq21.33 with a lod score of 2.56 at theta = 0.0 and marker DXS1108 in Xq28 with a lod score of 3.82 at theta = 0.0, Multipoint linkage analy sis showed that the odds for a location of the gene in Xq28 vs Xq21.33 are 100:1. This is the fourth family with non-specific X-linked menta l retardation with Xq28-qter as the most likely gene localization. (C) 1996 Wiley-Liss, Inc.