五例狭颅症患儿的基因学研究

摘要

目的 对中国籍汉族狭颅症患儿进行临床分子诊断,以发现相关致病基因.方法 运用高通量测序技术对2014年2月到2015年1月上海交通大学医学院附属上海儿童医学中心神经外科收治的5例狭颅症患儿进行外周血有核细胞基因全外显子组测序(WES),对所得数据进行生物信息学分析,并使用Sanger测序对WES发现的基因相关突变进行验证.结果 2例患儿上皮-间充质转变调控因子TWIST1基因的1号外显子分别存在一个杂合的错义变异:c.528C＞G,p.Ser176Arg和c.487C＞T,p.Leu163Phe;而另外3例患儿各存在1个成纤维细胞生长因子Ⅱ型受体(FGFR2)基因的杂合错义变异,其中2个位于7号外显子(c.755C ＞G,p.Ser252Trp和c.833G＞T,p.Cys278Phe),1个位于8号外显子(c.1 012G＞C,p.Gly338Arg).结论 借助于高通量DNA测序技术并结合临床特征,2例被诊断为TWIST1基因突变导致的Saethre-Chotzen综合征,2例被诊断为FGFR2基因突变导致的Crouzon综合征,另1例被诊断为FGFR2基因突变导致的Apert综合征.基因学研究有助于临床特征不显著的狭颅症患儿的确诊,可为狭颅症的诊断及分型提供依据.%Objective To conduct clinical molecular diagnosis for Chinese Han nationality children with craniostenosis in order to find the related pathogenic genes.Methods Five children with craniostenosis admitted to the Department of Neurosurgery,Shanghai Children' s Medical Center of Shanghai Jiao Tong University conducted whole-exome sequencing (WES) on peripheral blood nucleated cell genes using the high-throughput WES between February 2014 and January 2015.The obtained data were used conduct bioinformatic information analysis,and Sanger sequencing was used to validate the gene related mutation found by WES.Results The exon 1 of the regulator of epithelial-mesenchymal transition TWIST1 of 2 children had a heterozygous missense mutation respectively:c.528C ＞ G,p.Ser176Arg 和 c.487C ＞T,p.Leu163Phe;the other 3 children had a fibroblast growth factor receptor 2 (FGFR2) gene heterozygous missense mutation respectively.Two of them were located in the exon 7 (c.755C ＞ G,p.Ser252Trpand c.833G ＞T,p.Cys278Phe);and 1 was located in the exon 8 (c.1 012G ＞ C,p.Gly338Arg).Conclusions With the aid of high-throughput DNA sequencing technology and combined with clinical features,2 children were diagnosed as Saethre-Chotzen syndrome caused by TWIST1 mutation;2 were diagnosed as Crouzon syndrome caused by FGFR2 mutation,and 1 was diagnosed as Apert syndrome caused by FGFR2 mutation.Genetic studies contribute to diagnose the children with craniostenosis whose clinical feature is not significant,and provide the basis for the diagnosis of craniostenosis and typing.