Connexin 50 mutation in a family with congenital "zonular nuclear" pulverulent cataract of Pakistani origin

• DOI: 10.1007/s004390051082
• Publication Date: 2002-08-25T09:25:39Z
• Authors: V. Berry; D. Mackay; S. Khaliq; P.J. Francis; A. Hameed; K. Anwar; S. Qasim Mehdi; R.J. Newbold; A. Ionides; A. Shiels; T. Moore; S.S. Bhattacharya
• Keywords: Genetic linkage

Inherited cataract is a clinically and genetically heterogeneous disease that most often presents as a congenital autosomal dominant trait. Here we report linkage of a three-generation family of Pakistani origin with autosomal dominant cataract "zonular nuclear" pulverulent type (CZNP) on chromosome 1q21.1. Genome wide-linkage analysis excluded all the known cataract loci except on chromosome 1q. Significantly positive 2-point lod score values (Z=3.01 at theta=0) were obtained for markers D1S305 and D1S2721, which are known to flank the gene for connexin 50 (Cx50) or gap junction protein alpha-8 (Gja8). Previously a mutation in this gene has been reported in a British family with zonular pulverulent cataract (CZP). Here we describe a second mutation (E48K) in connexin 50 that confirms the involvement of this gene in cataractogenesis.