目的　总结低磷酸酯酶症（HPP）的临床及遗传学特点。方法　回顾分析5 例HPP患儿的临床资料，以及患 儿及其亲属的外周血高通量测序及Sanger验证结果。结果　5例患儿均有骨骼矿化不良以及血清碱性磷酸酶降低， 3例伴 有惊厥等神经系统症状。 5例HPP患儿高通量测序共发现ALPL6个突变位点，c.346G>A（p.A116T）、c.1097至c.1099del CCT复合杂合突变（p.T366_S367deli）、c.1014至c.1015ins G（p.H338fs）、c.1446C>A（p.482H>Q）复合杂合突变、c.920C>T （p.P307L）、c.883A>G（p.M295V），其中c.1014_c.1015ins G、c.1097_c.1099del CCT、c.1446C>A为首次报道，蛋白质结 构预测均为可能有害，ACMG评级为可能致病。结论　确诊5例HPP患儿，发现 3种新型突变，丰富了人类ALPL基因突变 数据库。

e　To summarize the clinical and genetic characteristics of hypophosphatasia (HPP). Methods　The clinical data and results of peripheral blood high-throughput sequencing in 5 children with HPP as well as Sanger verification of the children and their relatives were retrospectively analyzed. Results　All 5 patients had poor bone mineralization and decreased serum alkaline phosphatase, and 3 patients had nervous system symptoms such as convulsion. Six mutation sites were identified in these 5 children by high-throughput sequencing, including c.346G>A (p.A116T), c.1097 to c.1099del CCT complex heterozygous mutation (p.T366_S367deli), c.1014 to c.1015ins G (p.H338fs), c.1446C>A (p.482H>Q) compound heterozygous mutations, c.920C>T (p.P307L) and c.883A>G (p.M295V). Among them, c.1014-c.1015ins g, c.1097-c.1099del CCT and c.1446c> A were reported for the first time. Protein structure was predicted to be potentially harmful, and ACMG rates them as possibly pathogenic. Conclusions　Five children were diagnosed with HPP and three new mutations were found, which enriched the human ALPL gene mutation database.