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Mutation of the gap junction protein alpha 8 (GJA8) gene causes autosomal recessive cataract.

ABSTRACT: BACKGROUND: GJA8 encodes connexin-50, a gap junction protein in the eye lens. Mutations in GJA8 have been reported in families with autosomal dominant cataract. OBJECTIVE: To identify the disease gene in a family with congenital cataract of autosomal recessive inheritance. METHODS: Eight candidate genes were screened for pathogenic alterations in affected and unaffected family members and in normal unrelated controls. RESULTS: A single base insertion leading to frameshift at codon 203 of connexin 50 was found to co-segregate with disease in the family. CONCLUSIONS: These results confirm involvement of GJA8 in autosomal recessive cataract.

SUBMITTER: Ponnam SP

PROVIDER: S-EPMC2598012 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Mutation of the gap junction protein alpha 8 (GJA8) gene causes autosomal recessive cataract.

Ponnam Surya Prakash G SP Ramesha Kekunnaya K Tejwani Sushma S Ramamurthy Balasubramanya B Kannabiran Chitra C

Journal of medical genetics 20070701 7

<h4>Background</h4>GJA8 encodes connexin-50, a gap junction protein in the eye lens. Mutations in GJA8 have been reported in families with autosomal dominant cataract.<h4>Objective</h4>To identify the disease gene in a family with congenital cataract of autosomal recessive inheritance.<h4>Methods</h4>Eight candidate genes were screened for pathogenic alterations in affected and unaffected family members and in normal unrelated controls.<h4>Results</h4>A single base insertion leading to frameshif ...[more]

PMID: 17601931

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