Linkage analysis in an autosomal dominant 'zonular nuclear pulverulent' congenital cataract, mapped to chromosome 13q11-13

Purpose To determine by linkage analysis the chromosomal locus responsible for autosomal dominant congenital cataract (ADCC) in a four-generation Wels h pedigree. Methods The family pedigree was traced through two members of the family at tending the hospital for treatment of their cataracts. Twenty-five members of the family were examined ophthalmologically and blood was collected with consent for genetic linkage analysis. Results Fifteen members of this family were known to have bilateral congeni tal cataracts, of whom 11 had a cataract extraction prior to examination. T he youngest member of the pedigree was 5 years old and the oldest was 78 ye ars old. Four children, unoperated at the time of this study, had a phenoty pically identical morphology of their zonular pulverulent congenital catara cts. The known loci for congenital cataract were excluded. Significant lod scores for markers in the 13q11-13 region were detected with a Z(max) of 3. 59 D13S1236 (theta = 0.00). Conclusions We report linkage of an ADCC of the zonular pulverulent type to chromosome 13q11-13 in a four-generation family.