SYNGAP1基因移码变异所致精神发育迟滞患儿1例的遗传学分析

A case of mental retardation caused by a frameshift variant SYNGAP1 gene

目的探讨1例精神发育迟滞患儿的遗传学病因。方法选取2020年8月6日于广州中医药大学附属南海妇产儿童医院就诊的1例精神发育迟泄患儿为研究对象。用全外显子组测序技术对患儿及其父母进行变异筛查,结合临床资料分析可能的致病变异,并通过Sanger测序进行验证。结果基因测序提示患儿携带SYNGAP1基因杂合移码变异c.995_1002delAGACAAAA(p.Asp332AlafsTer84),其父母未携带相同变异。结论SYNGAP1基因c.995_1002delAGACAAAA(p.Asp332AlafsTer84)移码变异可能是患儿精神发育迟滞的遗传学原因。上述发现丰富了SYNGAP1基因的变异谱,为患儿的诊断和治疗提供了依据。

Objective To explore the genetic basis for a child with mental retardation.Methods Whole exome sequencing was carried out for the child.Candidate variant was screened based on his clinical features and verified by Sanger sequencing.Results The child was found to harbor a c.995_1002delAGACAAAA(p.Asp332AlafsTer84)frameshift variant in the SYNGAP1 gene.Bioinformatic analysis suggested it to be pathogenic.The same variant was not detected in either parent.Conclusion The c.995_1002delAGACAAAA(p.Asp332AlafsTer84)frameshift variant of the SYNGAP1 gene probably underlay the mental retardation in this child.Above finding has expanded the spectrum of SYNGAP1 gene variants,and provided a basis for the diagnosis,treatment for this child.