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目的:探讨1例Xq13.1缺失致n EDA基因部分缺失的少汗性外胚层发育不良的临床表型及遗传学特点。n 方法:分析1例少汗性外胚层发育不良患儿的临床资料，并进行染色体核型、家系全外显子组测序(trio-whole exome sequencing, trio-WES)、基因组拷贝数变异检查(copy number variations，CNV-seq)，对分析得到的可疑致病位置进行父母验证，明确异常基因变异来源。结果:先证者，男，7岁8月龄。头发稀少卷曲，眉毛浅淡稀疏，皮肤干燥，自幼易发热，少汗/无汗，牙齿尖、稀疏/部分缺失，鞍状鼻，前额突出，耳廓内收，癫痫发作。先证者常规染色体核型检查、全外显组测序未见异常；基因组拷贝数变异检查结果显示Xq13.1q13.1 (chrX：g.68 796 566-69 138 468)位置存在约341.90 kb缺失，包含有n EDA基因部分片段。经验证缺失区域来自先证者母亲，其临床表型为毛发正常，皮肤稍干燥，牙齿稀疏、脱落、钉状牙，基因组拷贝数变异检查检测到Xq13.1q13.1(chrX：g.68 836 154-69 078 250)位置存在约242.10 kb杂合缺失。n 结论:先证者及其母亲均存在Xq13.1缺失致n EDA基因部分片段缺失，母亲临床表型较轻，先证者临床症状较重，符合X连锁隐性遗传少汗性外胚层发育不良发病特点，n EDA基因部分缺失很可能是导致先证者出现异常临床表型的原因。n “,”Objective:To investigate the clinical phenotype and genetic characteristics of a patient with hypohidrotic ectodermal dysplasia (HED) due to partial deletion of n EDA gene.n Methods:The child has presented with HED complicated with epilepsy. Family trio whole exome sequencing (Trio-WES), copy number variation sequencing (CNV-seq), and karyotype analysis were carried out to explore the underlying genetic etiology.Results:The proband, a 7-year-and-8-month-old boy, presented with thin curly hair, thin and sparse eyebrow xerosis cutis, susceptibility to hyperthermia from childhood, hypohidrosis, sharp/sparse/absent teeth, saddle nose, prominent forehead, auricle adulation and seizure. He was found to have a normal chromosomal karyotype, and no abnormality was found by Trio-WES. Genome-wide CNV-seq revealed a 341.90 kb deletion at Xq13.1q13.1 (chrX: 68 796 566-69 138 468). As verified by PCR-electrophoresis, the deletion has removed part of the n EDA gene. The deletion was derived from his mother with normal hair, mild xerosis cutis, sparse, decidulated and nail-like teeth. The mother was detected with a heterozygous 242.10 kb deletion at Xq13.1q13.1 (chrX: 68 836 154-69 078 250).n Conclusion:Both the proband and his mother carried a Xq13.1 microdeletion involving part of the n EDA gene. The clinical phenotypes of the mother and the proband were consistent with the clinical characteristics of X-linked recessive HED, for which partial deletion of the n EDA gene is probably accountable.n