1例基因KIF1A错义突变致常染色体显性智力障碍9型病例报道

A Case Report of Autosomal Dominant Mental Retardation Type 9 caused by a Missense Mutation in Gene KIF1A

目的通过系统遗传学分析揭示1例KIF1A基因突变是导致常染色体显性遗传智力障碍9型的原因。方法采用全外显子基因测序方法对昆明市儿童医院收治的5岁语言发育迟缓,走路不稳易跌倒患儿及家系进行检测,后经Sanger验证及家系分析。结果KIF1A基因的变异位点是导致患儿常染色体显性智力障碍9型致病原因;找到了导致该病的KIF1A基因一个新发致病位点c.914C>T(p.Pro305Leu)的错义突变。结论证实了全外显子检测是诊断该病的关键方法;丰富了K1F1A基因致病突变谱和表型特征;同时发现一个遗传病家族成员中可能同时存在多个遗传学病因。

Objective Systematic genetic analysis revealed that the mutation of KIF1A gene was the cause of autosomal dominant mental disorder type 9(MRD9).Methods In this study,whole exome sequencing(WES)method was used for detection a 5 year old patient in our hospital were tested for language development retardation,unstable walking and easy to fall.Results The study found that the newly discovered mutation site of the KIF1A gene is the cause of autosomal dominant mental disorder type 9 in the patient.A new pathogenic missense mutation site of the KIF1A gene c.914C>T.(p.Pro305 Leu)that caused the disease was found.Conclusion It is confirmed that WES detection is critical method for diagnosing of MRD9,enriching the K1F1A gene s pathogenic locus spectrum and phenotypic characteristics.At the same time,it finds that there may be multiple genetic causes in a family member of a genetic disease.