Thymidine phosphorylase gene mutation is not a primary cause of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)
Thymidine phosphorylase gene mutation is not a primary cause of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)
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DOI：
10.2169/internalmedicine.45.1371
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发表时间：
2006-01-01
影响因子：
1.2
通讯作者：
Yamamoto, Teiji
中科院分区：
文献类型：
--
作者：
Kumagai, Yukie;Sugiura, Yoshihiro;Yamamoto, Teiji
目的报告1例线粒体神经胃肠脑肌病（MNGIE）患者，其胸苷磷酸化酶（TP）活性降低，完全符合临床诊断标准。然而，同样的纯合子S471 L TP基因突变也被发现在她的健康母亲，但正常的TP活性。方法采用直接测序和限制性片段长度多态性（RFLP）分析方法，对先证者和145例无关个体的TP基因突变进行分析。结果在145例正常人中，TP S471 L纯合子突变率为2.76%，其酶活性正常，结论TP基因突变不是MNGIE的主要病因，但存在线粒体缺失突变，TP基因单核苷酸多态性（SNP）可能在MNGIE的发病中起重要作用。
Objective The authors identified a patient with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), who completely fulfilled the clinical criteria with low thymidine phosphorylase (TP) activity. However, the same homozygotic S471L TP gene mutation was also found in her unaffected mother, but with normal TP activity. To elucidate the pathogenesis of MNGIE, we performed the analysis below.Methods We analyzed the TP gene mutation in the proband and 145 unrelated individuals by direct sequence and restriction fragment length polymorphism (RFLP). TP activity was determined by the spectrophotometric method for each TP S471L genotype.Results Among 145 normal persons, the S471L homozygote mutants were identified in 2.76% and their enzyme activity was normal.Conclusion TP gene mutation is not a primary cause of MNGIE, but with a mitochondrial deletion mutation, a single nucleotide polymorphism (SNP) of the TP gene may be crucial in the pathogenesis of MNGIE.