CAJ | 학술논문

目的对1例脊肌萎缩症(spinal muscular atrophy,SMA)患者及其家系成员的SMN基因行突变分析.方法采用多重连接依赖性探针扩增(multiplex ligation-dependent probe amplification,MLPA)技术、逆转录聚合酶链反应及T克隆-测序技术对患者SMN基因进行拷贝数分析和点突变的鉴定,应用MLPA和针对点突变区域的SMN基因第5外显子PCR-直接测序法对患者父母SMN基因进行拷贝数分析和点突变的证实,同时用200名正常人外周血进行相关位点对照研究.结果患者具有1个拷贝的SMNl基因和1个拷贝的SMN2基因,在这个SMNl基因第230位密码子上存在1个未见报道的错义突变S230L(TCA→TTA);父亲具有两个SMN1和两个SMN2拷贝,其中1个SMNl基因存在S230L突变;母亲具有1个SMN1拷贝,而SMN2基因是纯合缺失的.200名对照中未发现该位点突变.结论在1个SMA家系中发现了1个新的SMNI基因点突变,即S230L,并准确分析了此家系各成员的SMN基因型.
목적 대1례척기위축증(spinal muscular atrophy,SMA)환자급기가계성원적SMN기인행돌변분석.방법 채용다중련접의뢰성탐침확증(multiplex ligation-dependent probe amplification,MLPA)기술、역전록취합매련반응급T극륭-측서기술대환자SMN기인진행고패수분석화점돌변적감정,응용MLPA화침대점돌변구역적SMN기인제5외현자PCR-직접측서법대환자부모SMN기인진행고패수분석화점돌변적증실,동시용200명정상인외주혈진행상관위점대조연구.결과 환자구유1개고패적SMNl기인화1개고패적SMN2기인,재저개SMNl기인제230위밀마자상존재1개미견보도적착의돌변S230L(TCA→TTA);부친구유량개SMN1화량개SMN2고패,기중1개SMNl기인존재S230L돌변;모친구유1개SMN1고패,이SMN2기인시순합결실적.200명대조중미발현해위점돌변.결론 재1개SMA가계중발현료1개신적SMNI기인점돌변,즉S230L,병준학분석료차가계각성원적SMN기인형.
Objective To perform mutation analysis and describe the genotype of the SMN gene in a patient with spinal muscular atrophy (SMA) and his family. Methods Deletion analysis of the SMN1 exon 7 by conventional PCR-restriction fragment length polymorphism(RFLP) and allele-specific PCR, and gene dosage of SMN1 and SMN2 by multiplex ligation-dependent probe amplification (MLPA) were performed for the patient and his parents; reverse transcriptase(RT)-PCR and sequencing were performed for the patient. To determine whether the SMN variant was exclusive to transcripts derived from SMN1, the RT-PCR product of the patient was subcloned and multiple clones were sequenced directly; PCR of SMN exon 5 from the genomic DNA of the parents and direct sequencing were performed to confirm the mutation. Results In SMN1 exon 7 deletion analysis, no homozygous deletion of the SMN1 was observed in the family; the gene dosage analysis by MLPA showed that the patient had 1 copy of SMN1 and 1 copy of SMN2, his father had 2 copies of SMN1 and 2 copies of SMN2, and his mother had 1 copy of SMN1 and no SMN2. A previously unreported missense mutation of S230L was identified from the patient and this mutation was also found in his father. Conclusion A novel missense mutation of S230L was identified in the SMA family and the genotype of the family members were in vestigated.