逆遗传方向研究男性G6PD缺乏症及其母亲的表型与基因型

Phenotypes and genotypes of glucose-6-phosphate dehydrogenase deficiency in mothers and sons by reverse genetics

目的分析女性G6PD酶活性检测真实的漏检率以及女性G6PD酶活性与基因突变的关系。方法收集124名男性确诊为G6PD缺乏症半合子,收集其母亲标本,荧光斑点试验和硝基四氮唑蓝法分别进行G6PD酶活性筛查与酶活性直接测定,探针熔解曲线分析技术检测中国人常见G6PD基因突变。结果所有男性子代G6PD酶活性介于1.10～8.58 U/gHb;母亲酶活性介于1.44～31.20 U/gHb;男性子代G6PD基因检测中除1例外,均检出G6PD基因突变,其母亲除1例未检出突变外,余均检出突变。母亲酶活性正常占70.2%(87/124),仅检测出单一突变;母亲酶活性中度/轻度缺乏者占16.1%(20/124),除2例为双重基因突变外,余均为单一突变;母亲G6PD重度缺乏者占13.7%(17/124)均检测为双重突变(其中一例推算为双重杂合子)。结论女性携带单一突变基因,酶活性呈连续性大跨度分布,表型筛查检出率低;男性酶活性仅约为携带相同基因突变女性的1/6。女性携带双重突变者严重影响G6PD酶活性,与男性半合子相当。女性筛查优先采用分子诊断技术可减少大量病例漏诊。

Objective To investigate the true detection rate of female G6PD enzyme activity, the relationship between G6PD enzyme activity and gene mutation in women. Methods 124 males with G6PD deficiency and their mothers were collected. The G6PD enzyme activity screening and enzyme activity were detected by fluorescent spot test and nitroblue tetrazoliun test. The melting curve analysis technique was used to detect the Chinese common G6PD gene mutation. Results The G6PD enzyme activity of all male was 1.10-8.58 U/gHb. The mothers′ enzyme activity was 1.44-31. 20 U/gHb. Common G6PD gene mutations were detected in male offspring like their mothers except for one case, 70.2%(87/124) of mothers had normal enzyme activity, with a single mutation;while 16.1%(20/124) of mothers had moderate/mild deficiency with a single mutation except for 2 cases with double gene mutations;13.7%(17/124) of mothers with severe G6PD deficiency were detected as double mutations(one case was double heterozygote). Conclusion Women with a single mutation gene, the enzyme activity showed a continuous large-span distribution;male enzyme activity was only 1/6 as women with the same gene mutation. Women with double mutations seriously affect the activity of G6PD enzyme, like male hemizygous. So genetic screening was necessary.