中国人遗传性高铁血红蛋白血症NADH—细胞色素b5还原酶基因L …

目的：鉴定导致中国人遗传性高铁血红蛋白血症（ＲＣＭ）的ＮＡＤＨ－细胞色素ｂ５还原酶（ｂ５Ｒ）基因突变类型，探讨ＲＣＭ发病的分子基础。方法：逆转录－聚合酶链反应产物直接测序和ｃＤＮＡ克隆测定分析先证者的ｂ５Ｒ编码基因，限制性酶切分析其基因组ＤＮＡ。结果；发现一例ＲＣＭ患者ｂ５Ｒ基因第７２密码子存在新的错义突变（ＣＴＣ→ＣＣＣ）。结论：该突变导致ｂ５Ｒ蛋白第７２位亮氨酸被脯氨酸替换（Ｌ７２Ｐ）是该先证

Leu 72 Pro mutation in the NADH-cytochrome b5 reductase gene found in a Chinese hereditary methemoglobinemia patient]

OBJECTIVE: To characterize the mutation in NADH-cytochrome b5 reductase gene in a Chinese hereditary methemoglobinemia patient, and elucidate the molecular basis of the disease. METHODS: B5R gene from a propositus was analyzed by sequencing the RT-PCR products as well as cDNA clones; and the results were further confirmed by restriction enzyme analysis of the genomic DNA fragments. RESULTS: A novel mutation was found at codon 72 of b5R gene from the propositus. CONCLUSION: Replacement of Leu with Pro at codon 72 of b5R gene is the molecular basis of the propositus; and the mutant allele located in 5' part of b5R gene mainly cause hereditary methemoglobinemia type I.