A CRYGC Mutation Associated With Autosomal Dominant Congenital Cataract In A Chinese Family

Objective:1. To establish paper and electronic records of clinical data and blood samplesdatabase to collect and preserve the genetic resources of congenital cataract.2. To analyze the clinical and genetic features of a congenital cataract familynamed HN-DZ001and to find the pathogenic gene mutation.Methods:1. Collecting and preserving clinical resources of HN-DZ001family includingsigning the informed consent, filling out congenital cataract questionnaire, drawingthe pedigree. The13subjects (6affected individuals and7unaffected individuals)were collected the family’s medical history, including the onset of the eyes, visual lossand other surgical history, etc. Eye examinations include visual acuity, intraocularpressure, Lens, fundus, visual field. Analyzing the Phenotype and determining themode of inheritance. Extracting genomic DNA from8ml peripheral blood, which iscompleted in the laboratory.2. All the exons of five congenital cataract candidate genes CRYAA、CRYGC、MIP、 GJA3and GJA8were amplified by polymerase chain reaction (PCR) andbidirectional sanger sequencing.3.Candidate mutations were validated in affected family members and100normalunaffected individuals using Sanger Sequencing.Results:1.There are7surviving patients in the family with27members of threegenerations, including two male and five female. Based on the patients’ clinicalphenotype (Coppock-like cataract), the pattern of inheritance was consistent withautosomal dominant. 2.Sequence analysis of CRYGC revealed a missense mutation in exon2(c.13A＞C) in the6affected patients. This mutation (c.13A＞C) resulted in the codingsequence, which change the ACC codon for threonine to a CCC codon forproline(Thr5Pro). At the same time, no mutation was found in four candidate genes(CRYAA、MIP、GJA3and GJA8) in the members of HN-DZ001family,Conclusion:1. The HN-DZ001family was autosomal dominant congenital cataract family.Coppock-like cataract is the characteristic manifestations of the disease.2. The missense mutation, c.13A＞C in exon2of CRYGC was the pathogeneticgene mutation of HN-DZ001family, which is a well-known mutation.