Next-generation sequencing (NGS) has greatly advanced the studies of causative genes and variants of inherited diseases. While it is sometimes challenging to determine the pathogenicity of identified variants in NGS, the American College of Medical Genetics and Genomics established the guidelines to help the interpretation. However, as to the genetic screenings for patients with retinitis pigmentosa (RP) in Japan, none of the previous studies utilized the guidelines. Considering that EYS is the major causative gene of RP in Japan, we conducted stepwise genetic screening of 220 Japanese patients with RP utilizing the guidelines. Step 1–4 comprised the following, in order: Sanger sequencing for two major EYS founder mutations; targeted sequencing of all coding regions of EYS; whole genome sequencing; Sanger sequencing for Alu element insertion in RP1, a recently determined founder mutation for RP. Among the detected variants, 2, 19, 173, and 1 variant(s) were considered pathogenic and 8, 41, 44, and 5 patients were genetically solved in step 1, 2, 3, and 4, respectively. Totally, 44.5% (98/220) of the patients were genetically solved, and 50 (51.0%) were EYS-associated and 5 (5.1%) were Alu element-associated. Among the unsolved 122 patients, 22 had at least one possible pathogenic variant.

下一代测序（NGS）极大地推动了致病基因和遗传疾病变异的研究。虽然确定NGS中已鉴定变体的致病性有时具有挑战性，但美国医学遗传学和基因组学学院建立了指导原则以帮助解释。但是，对于日本的色素性视网膜炎（RP）患者的基因筛查，以前的研究均未使用该指南。考虑到EYS是日本RP的主要致病基因，我们根据指南对220例日本RP患者进行了逐步遗传筛选。步骤1-4按顺序包括以下内容：两个主要EYS创建者突变的Sanger测序；的所有编码区的靶向测序EYS; 全基因组测序；用于在RP1中确定Alu元素插入的Sanger测序，RP1是最近确定的创始人突变。在检测到的变体中，有2、19、173和1个变体被认为是致病的，分别在步骤1、2、3和4中遗传了8、41、44和5例患者。总共有44.5％（98/220）的患者获得了基因解决，其中50例（51.0％）与EYS相关，5例（5.1％）与Alu元素相关。在未解决的122位患者中，有22位具有至少一种可能的致病变异。