Novel mutations in in Bietti corneoretinal crystalline dystrophy: Next-generation sequencing technology and genotype-phenotype correlations.

Purpose: To identify any novel mutations in in 85 Chinese families with Bietti corneoretinal crystalline dystrophy (BCD) by using next-generation sequencing, and to summarize the mutation spectrum in this population, along with any genotype-phenotype correlations.

Methods: A total of 90 patients with BCD from 85 unrelated Chinese families were recruited. All probands were analyzed by using gene chip-based next-generation sequencing, to capture and sequence all the exons of 57 known hereditary retinal degeneration-associated genes. The candidate variants were validated with PCR and Sanger sequencing.

Results: Twenty-eight mutations were detected in all patients, including thirteen novel mutations (five missense, six deletions, one splicing and one frame-shift mutations) and 15 previously reported mutations. Mutations in 64 patients were inherited from their parents, while three patients had de novo mutations. c.802-8_810del17insGC was the most common mutation, accounting for 78% of the mutations. Although 16 patients were homozygous at this site, the clinical features of all 16 patients were highly heterogeneous.

Conclusions: These results expand the spectrum of mutations in , and suggest that mutations in may be common in the Chinese population. The phenotype of patients with the homozygous mutation (hom.c.802-8_810del17insGC) is highly heterogeneous.