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目的:探讨全色盲一家系的致病基因突变。方法:采用家系调查研究方法，于2018年11月对河南省立眼科医院收集的来自河南省洛阳市的汉族全色盲一家系进行基因测序。详细采集患者的病史资料，对患者及其家系成员进行最佳矫正视力(BCVA)测定，采用裂隙灯显微镜和前置镜检查眼前节和眼底，采用客观和主觉验光法对受检者进行屈光度检查，采用孟塞尔色觉测试工具Munsell FM 100进行色觉检查，采用国际标准化5项全视野闪光视网膜电图(FERG)评估视网膜功能，采用眼底照相仪进行眼底照相，采用频域光相干断层扫描成像(SD-OCT)观察受检者视网膜结构。采集先证者(Ⅲ1)及其胞弟(Ⅲ2)、父母的外周静脉血各4 ml提取全基因组DNA，采用包含441个致病基因的遗传眼病捕获芯片进行靶向捕获富集高通量测序。由于未检测到有意义的致病基因及突变，因此将Ⅲ1、Ⅲ2及其父母的DNA进行人全基因组测序。测序数据通过与疾病相关的数据库进行比对，对受检者的DNA进行Sanger测序并对其结果进行生物信息学分析。结合家系图与先证者进行共分离分析。结果:该全色盲家系包括三代10名成员，患病者2例，遗传方式符合常染色体隐性遗传模式。Ⅲ1及Ⅲ2均表现为自幼发生的、与年龄增长无关的视力低下和畏光；眼底检查可发现视网膜色素沉积；SD-OCT检查示双眼黄斑区外界膜及椭圆体带反射信号欠规则；色觉检查示双眼全色盲。FERG示患者双眼暗视0.01、3.0和10.0 ERG a、b波振幅及振荡电位轻度下降，明视ERG a、b波振幅及30 Hz ERG各波振幅严重下降。Ⅲ1和Ⅲ2存在n CNGB3基因1个新的突变位点c.129＋1G>A和1个已知的突变位点c.1285dupT组成的复合杂合突变。n 结论:CNGB3基因c.129＋1G>A和c.1285dupT的复合杂合突变可能是本家系的致病原因，该家系成员在n CNGB3基因2个位点同时出现变异时才表现出临床症状。n “,”Objective:To identify the pathogenic gene mutations in a Chinese achromatopsia family.Methods:A pedigree investigation was performed.A Chinese Han pedigree from Luoyang city of China was enrolled in Henan Eye Hospital in November 2018.The medical history of the patients was collected.The best corrected visual acuity (BCVA) of the families was examined.The maniafestations of the anterior segment and fundus were obtained via slit lamp biomicroscope and slit lamp lens.The diopter was determined by objective and subjective refraction.Color vision was examined by Farnsworth-Munsell Hue Test.Retinal function was evaluated by international standard electroretinogram (ERG). Retina was observed by color photography, and its structural image was obtained by spectral-domain optical coherence tomography (SD-OCT). The peripheral blood sample was collected from the proband (Ⅲ1) and her younger brother (Ⅲ2) and parents for whole blood DNA extraction, and a whole genome sequencing (WGS) was performed to identify the pathogenic genes and mutation sites, and the sequencing data was compared through disease-related databases such as the Human Genome Databases due to a negative detective result of specific hereditary eye disease enrichment panel based on targeted exome capture technology.Sanger sequencing and bioinformatics analysis was carried out with softwares.The cosegregation analysis was performed.This study protocol was approved by an Ethics Committee of Henan Eye Hospital (No.HNEECKY-2019[15]) and complied with Declaration of Helsinki.Written informed consent was obtained from each subject or the guardian before any medical examination.Results:This family included 2 patients and 8 members with normal phenotypes in 3 generations and showed an autosomal recessive inheritance model.Poor vision and photophobia appeared after birth in both Ⅲ1 and Ⅲ2, and these symptoms did not deteriorate with aging.Pigmentary mottling and atrophic changes could be seen in the retinas of the patients.Reflection bands of external membrane and ellipsoid line in macula of patients were irregular on the OCT image.Color vision examination showed achromatopsia of the patients.ERG indicated that the amplitudes of a-, b-waves of scotopic 0.01, 3.0, 10.0 ERG and oscillatory potentials were slightly reduced, and the amplitudes of a-, b-waves of photopic ERG and wavelets of 30 Hz were seriously reduced in both eyes of Ⅲ1 and Ⅲ2.WGS showed that heterozygous mutations of a novel mutation c. 129+ 1G>A and a known mutation c. 1285dupT of CNGB3 gene in Ⅲ1 and Ⅲ2.The mutations were confirmed by Sanger sequencing.Conclusions:The compound heterozygous mutation in c. 129+ 1G>A/c.1285dupT of CNGB3 gene may be responsible for the achromatopsia pathogenesis in this Chinese Han pedigree.The abnormal phenotype of the patients is the result of both CNGB3 c. 129+ 1G>A and CNGB3 c. 1285dupT mutations simultaneously.