遗传性痉挛性截瘫一家系的临床特点与spastin基因突变分析

目的　探讨常染色体显性遗传的遗传性痉挛性截瘫 (SPG)一家系的临床特点,并行spastin基因突变分析。方法　对整个家系进行详细的临床检查,先证者和另一例家系内患者进行了心肌酶学、头颅核磁共振成像(MRI)、胸髓MRI、肌电图、体感诱发电位检查。应用聚合酶链式反应 单链构象多态性(PCR SSCP)结合DNA序列分析方法,检测该家系中所有 5例患者和 4名有血缘关系的健康人及家系外 50名无血缘关系健康对照者spastin基因的突变情况。结果　先证者和家系内另一例SPG患者胸髓MRI显示胸髓萎缩;PCR SSCP检测发现家系内患者均出现异常SSCP电泳带,经测序证实为Leu378Gln突变。结论　该常染色体显性遗传SPG家系的患者具有典型的临床表现,为spastin基因Leu378Gln突变所致。

Clinical characteristics and spastin gene mutation analysis on an autosomal dominant kindred with hereditary spastic paraplegia

Objective To investigate the clinical characteristics and analyze spastin gene mutation on an autosomal dominant kindred with hereditary spastic paraplegia (SPG).Methods All family members were studied through clinical examinations, the proband and another patient in this kindred were subjected to serum enzymes, cranial and thoracic MRI, electromyography (EMG) and somatosensory evoked potential (SSEP) examinations. Mutation analysis of spastin gene was screened by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) combined with DNA direct sequencing in five patients, four unaffected family members and 50 unrelated normal controls.Results Thoracic MRI revealed atrophies of the spinal cord in the proband and another patient in this kindred. Abnormal SSCP and Leu378Gln mutations were identified in the 5 patients.Conclusion The kindred caused by mutation of spastin gene had typical clinical symptoms of SPG. Using PCR-SSCP combined with DNA direct sequencing can make gene diagnosis to SPG that is caused by spastin gene mutations.