目的:对2例限制型心肌病患儿进行高通量测序，明确其可能的致病原因。方法:提取患儿及其父母外周血基因组DNA，进行目标基因或全外显子测序并进行生物信息学分析，筛查与心肌病相关致病基因变异，并用Sanger测序法进行位点验证。结果:例1存在n TNNI3基因c.549+1G>T杂合变异，父母未检出该变异，为新发变异，且目前未见报道，根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics, ACMG)遗传变异分类标准与指南，判定为致病变异(PVS1+PS2+PM2)。例2和父亲的n TNNI3基因存在c.433C>T(p.Arg145Trp)杂合变异，Clinvar、HGMD数据库检索结果显示其为致病变异，根据ACMG标准与指南判定为可能致病变异(PS3+PM1+PP3)。n 结论:TNNI3基因变异可能为2例限制型心肌病患儿的致病原因，基因检测结果为患儿的临床诊断提供了依据。n “,”Objective:To identify the pathogenesis in two patients of restrictive cardiomyopathy (RCM) using high throughput sequencing.Methods:Peripheral blood samples from these two patients and their parents were collected and genomic DNAs were extracted to conduct targeted next-generation sequencing or whole exome sequencing. Bioinformation analysis was performed to identify the pathogenic variants in genes associated with cardiomyopathy , which were further validated by Sanger sequencing.Results:By high throughput sequencing, we detected a n de novo heterozygous variant c. 549+ 1G>T inn TNNI3 gene in patient 1. The variant has not been reported previously and was predicted to be pathogenic in line with American College of Medical Genetics and Genomics (ACMG) guidelines (PVS1+ PS2+ PM2). Another heterozygous variant c. 433C>T (p.Arg145Trp) inn TNNI3 gene was identified in patient 2 and his father. The variant had been reported as pathogenic variant in Clinvar and HGMD databases; based on ACMG guidelines, the variant was predicted to be likely pathogenic(PS3+ PM1+ PP3).n Conclusion:TNNI3 variants may be the causative gene responsible for restrictive cardiomyopathy in these two patients. High throughput sequencing results provide bases for the diagnosis of restrictive cardiomyopathy.n