Identification of a genetic locus for autosomal dominant infantile cataract on chromosome 20p12.1-p11.23 in a Chinese family

摘要

Purpose: To map a gene responsible forinfantile cataract in a large four-generation, non-consanguineousChinese family. Methods: Twenty-two family membersincluding 17 cataract patients in the Chinese family were analyzedclinically. All family members were genotyped with 382 microsatellitemarkers that provide genome-wide coverage every 10 cM. Linkage analysiswas performed to identify the chromosomal location of the infantilecataract gene in the family. Candidate genes were studied by direct DNAsequence analysis. Results: Genome-wide linkage analysisprovided evidence for a genetic locus for infantile cataract onchromosome 20p12.2-20p11.23. The maximum LOD score was 5.15 for markerD20S471 at a recombination fraction of 0. Fine mapping defined thecataract gene within a 7.4 Mb interval between markers D20S915 andD20S912. No mutation was detected in potential candidate genes, BFSP1and CHMP4B. Conclusions: Our results suggest thatthere is a new gene for infantile cataract on chromosome20p12.2-p11.23. Our results suggest that new genes for infantilecataract could be found through further study of candidate genes at the20q locus, which may provide insights into the pathogenic mechanisms ofcataracts.