Localisation of a new gene for non-specific mental retardation to Xq22-q26 (MRX35).
Non-specific mental retardation (MR) is a condition in which MR appears to be the only consistent manifestation. The X linked form (MRX) is genetically heterogeneous. We report clinical, cytogenetic, and linkage data on a family with X linked non-specific MR. Two point and multi-point linkage analysis with 18 polymorphic markers, covering the entire chromosome, showed close linkage to DXS1001 and DXS425 with a maximal lod score of 2.41 at 0% recombination. DXS178 and the gene for hypoxanthine phosphoribosyl-transferase (HPRT), located in Xq22 and Xq26 respectively, flank the mutation. All other chromosomal regions could be excluded with odds of at least 100:1. To our knowledge there is currently no other non-specific MR gene mapped to this region. Therefore, the gene causing MR in this family can be considered to be a new, independent MRX locus (MRX35).
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Centre for Human Genetics, University of Leuven, Campus Gasthuisberg, Belgium.
Decorte
R
R
Marynen
P
P
Fryns
J P
JP
Cassiman
J J
JJ
Raeymaekers
P
P
D002648:Child; D002675:Child, Preschool; D002874:Chromosome Mapping; D005260:Female; D030342:Genetic Diseases, Inborn / Q000235:genetics*; D005819:Genetic Markers / Q000235:genetics; D006239:Haplotypes; D006579:Heterozygote; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male; D010375:Pedigree; D014960:X Chromosome / Q000235:genetics*
D005819:Genetic Markers