MAPT基因突变导致行为变异型额颞叶痴呆部分家系分析

Partial family analysis of MAPT gene mutation leading to behavioral variant frontotemporal dementia

目的:报道1例微管相关蛋白-tau(microtubule-associated protein tau,MAPT)基因突变所致行为变异型额颞叶痴呆家系患者的临床表现、神经系统查体、家系图、神经心理学检测、头颅磁共振表现及基因检查特征,并进行文献复习。方法:收集行为变异型额颞叶痴呆(behavioral variant frontotemporal dementia,bvFTD)患者1例,进行询问病史、神经系统查体和神经心理学检查,并行常规化验、头颅磁共振表现及基因检查,并复习相关文献。结果:该例患者表现为突出的性格改变、行为异常下降,症状进行性加重,家族中两人有类似临床症状。患者头颅MRI提示双侧颞前极和顶叶对称性脑萎缩,海马萎缩较轻。基因检查提示MAPT基因c.915+16C>T杂合突变。报道bvFTD以社会行为异常、性格改变和认知功能持续性下降为主要表现,是FTLD中遗传性最强的亚型,MAPT基因是其最常见的致病基因之一。结论:本例bvFTD患者存在MAPT基因c.915+16C>T杂合突变,从而引发神经变性。对于临床诊断bvFTD的患者应完善基因学检测。

Objective:A case of behavioral variant frontotemporal dementia(bvFTD)caused by microtubule-associated protein tau gene mutation in a family was reported.The clinical manifestations,neurological examination,family map,neuropsychological examination,magnetic resonance imaging and genetic examination were examined and the literature was reviewed.Methods:A case of behavioral variant frontotemporal dementia was collected.The history,nervous system physical examination and neuropsychological examination were carried out.Routine tests,brain magnetic resonance imaging and gene examination were performed.The relevant literature was reviewed.Results:The patient presented with prominent personality changes,abnormal decline in behavior,and progressive exacerbation of symptoms.Two members of the family had similar clinical symptoms.The patient's head MRI showed symmetrical brain atrophy in bilateral anterior temporal pole andparietal lobe,and mild hippocampal atrophy.Genetic examination suggested heterozygous mutation of MAPT gene c.915+16C>T.BvFTD is the most hereditary subtype of FTLD,and MAPT gene is one of the most common pathogenic genes of bvFTD.Conclusion:Heterozygous mutation of MAPT gene c.915+16C>T exists in this patient with bvFTD,which leads to neurodegeneration.Genetic testing should be improved for patients with clinically diagnosed bvFTD.