常染色体显性遗传先天性核性白内障家系的致病基因突变研究

Study on the pathogenic gene mutation of a pedigree of autosomal dominant congenital nuclear cataract

目的对一个常染色体显性遗传先天性核性白内障家系的致病基因突变进行研究，探索其潜在的分子遗传学缺陷。方法选择一个确诊为常染色体显性遗传先天性核性白内障家系，随机选取家系中的6例白内障患者为实验组，6名有血缘关系的正常成员为对照组，常规采集外周血5ml，提取基因组DNA，应用PCR直接测序法对实验组和对照组的基因片断进行先天性核性白内障候选基因的突变检测，并对测序结果进行分析。结果实验组的GJA8基因出现了c．139G〉A的错义突变，对照组未出现该突变。结论在中国家系的GJA8基因外显子上发现了新的突变点（D47N），为研究先天性核性闩内障的分子发病机制、基因诊断和基因治疗提供了科学的理论依据。

Objective To study the mutations of pathogenic genes in a pedigree of autosomal dominant congenital nuclear cataract, and explore their potential defects in molecular genetics. Methods A pedigree diagnosed with autosomal dominant congenital nuclear cataract was selected, 6 cataract patients in the pedigree randomly chosen as experimental group, and 6 related normal members chosen as control group. 5 ml of peripheral blood was collected and genome DNA was extracted, The mutations of candidate gene were detected by PCR in direct sequencing in the experimental group and the control group, the results were analyzed. Result c.139G〉A hybrid missense mutation was found in Gene G JAB in the experimental group, but this change was not shown in the control group. Conclusion A new mutation spot （D47N） was found in GJA8 gene exon in Chinese pedigree, which provided a theoretical basis for pathogenesis, diagnosis, and therapy in congenital nuclear cataract research.