A novel truncation mutation in GJA1 associated with open angle glaucoma and microcornea in a large Chinese family.

PURPOSE: To identify genetic defects in a large family with open angle glaucoma (OAG) and microcornea.

METHODS

Genomic DNA was prepared from leukocytes of 15 individuals from three generations of a Chinese family, including seven individuals with OAG and microcornea, one with microcornea alone, and seven healthy individuals. Whole exome sequencing was performed on genomic DNA of the proband. Candidate variants were obtained through multiple steps of bioinformatics analysis and validated by Sanger sequencing and segregation analysis.

RESULTS

Exome sequencing detected a candidate variant in GJA1, a novel truncation mutation (c.791_792delAA, p.K264Ifs*43). This mutation was present in all seven individuals with OAG and microcornea and the individual with microcornea alone, but not in the seven unaffected relatives in the family. It was not present in 1394 alleles from 505 unrelated controls without glaucoma and 192 normal controls. Extraocular signs were not observed in seven out of the eight individuals; only one was affected with dental enamel hypoplasia and syndactyly.

CONCLUSIONS

A novel truncation mutation in GJA1 is associated with OAG and microcornea in a Chinese family. This suggests that GJA1 should be included as a candidate gene for glaucoma.