Linkage mapping of a nonspecific form of X-linked mental retardation (MRX53) in a large Pakistani family

nonprogressive, genetically heterogeneous condition that affects cognitive function in the absence of other distinctive clinical manifestations. We re port here linkage data on a large Pakistani family affected by a form of X- linked nonspecific mental retardation. X chromosome genotyping of family me mbers and linkage analysis allowed the identification of a new disease locu s, MRX53. The defined critical region spans approximately 15 cM between DXS 1210 and DXS1047 in Xq22.2-26. A LOD score value of 3.34 at no recombinatio n was obtained with markers DXS1072 and DXS8081. (C) 2001 Wiley-liss, Inc.