先天性视网膜劈裂症的RS1基因分析

Diagnosis and analysis of RS1 gene mutation in X-linked juvenile retinoschisis

目的观察先天性视网膜劈裂症的临床特征,研究患者的基因突变。方法采用聚合酶链反应(PCR)法,对先天性视网膜劈裂症一家系6名成员RS1基因的6个外显子各片段进行扩增,直接进行DNA测序分析,以明确突变位点及突变类型。结果先证者发生第625位核苷酸C→T,导致第209位氨基酸Arg→Cys。家系中有2名女性成员的外显子6核苷酸第625位的单碱基突变,为无临床症状和体征的突变携带者。结论本家系中先天性视网膜劈裂症患者是由RS1基因突变所致。

Background Congenital retinoschisis is also known as X-linked juvenile retinoschisis.Single strand conformation polymorphism （SSCP） analysis have demonstrated the mutation of 11 kinds of X-linked juvenile retinoschisis 1 gene in 12 Chinese families.Objective This survey was to observe the clinical feature of X-linked juvenile retinoschisis and analyze the mutation of gene in the families with X-linked juvenile retinoschisis and provide the information of genetic diagnosis and heredity consultation for the patients and their families.Methods The clinical examination,fluorescence fundus angiography（FFA）,optical coherence tomography （OCT） were performed in the members of one family with X-linked juvenile retinoschisis.Genomic DNA was isolated from leukocyte of 6 members.All 6 exons of X-linked juvenile retinoschisis 1 gene were amplified by polymerase chain reaction （PCR）.The position and type of X-linked juvenile retinoschisis 1 gene mutation was determined by direct sequencing.This trial was approved by the Ethic Committee of this hospital.Oral informed consent was obtained from the examinee prior to any medical protocol.Results Radical wrinkles in color photograph,the cystic changes and interlamellar rupture of retinal epitheliallayer in OCT,transmitted fluorescence of macular area in FFA.Arg209Cys mutation was detected on exon 6 in the proband and one gene carrier.This was the first report of this outcome in China.Conclusion Arg209Cys mutation is first found in X-linked juvenile retinoschisis family.It offers a new data for the genetic consultation and prenatal gene diagnosis.