Waardenburg syndrome (WS): the analysis of a single family with a WS1 mutation showing linkage to RFLP markers on human chromosome 2q.
Waardenburg syndrome type I (WS1; MIM 19350) is caused by a pleiotropic, autosomal dominant mutation with variable penetrance and expressivity. Of individuals with this mutation, 20%-25% are hearing impaired. A multilocus linkage analysis of RFLP data from a single WS1 family with 11 affected individuals indicates that the WS1 mutation in this family is linked to the following four marker loci located on the long arm of chromosome 2: ALPP (alkaline phosphatase, placental), FN1 (fibronectin 1), D2S3 (a unique-copy DNA segment), and COL6A3 (collagen VI, alpha 3). For the RFLP marker loci, a multilocus linkage analysis using MLINK produced a peak lod (Z) of 3.23 for the following linkage relationships and recombination fractions (theta i): (ALPP----.000----FN1)----.122----D2S3----.267----CO L6A3. A similar analysis produced a Z of 6.67 for the following linkage relationships and theta i values among the markers and WS1: (FN1----.000----WS1----.000----ALPP)----.123----D2S 3----.246----COL6A3. The data confirm the conclusion of Foy et al. that at least some WS1 mutations map to chromosome 2q.
Asher
J H
JH
Department of Zoology, Michigan State University, East Lansing 48824.
Morell
R
R
Friedman
T B
TB
D002889:Chromosomes, Human, Pair 2; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D014849:Waardenburg Syndrome / Q000235:genetics*
D005819:Genetic Markers