Molecular Characterization Of The Glucose-6-Phosphate Dehydrogenase Deficiency In The Han And Li Nationalities In Hainan, China

[Objective]Glucose-6-phosphate dehydrogenase(G6PD) deficiency is the most frequent genetic enzymopathy, mainly caused by mutations of G6PD gene. The purpose of this study is to further investigate the gene mutations at DNA levels and to elucidate the molecular basis of G6PD deficiency in the population of the Han and Li nationalities in Hainan ,China. [Methods]Quantitavite analysis of G6PD activity by nitroblue tetrazolium(NBT) method was used to screen the G6PD deficient patients in the populations of the Han and Li nationalities in Hainan. The amplification refractory mutation system(ARMS) method was employed to detecte the three common mutations of G1376T, G1388A and A95G of G6PD deficiency in the populations of the Han and Li nationalities. The second exon to the thirteenth exon of G6PD gene was analyzed by DNA sequencing to characterize the gene mutations of samples with unknown mutations. [Results]1. The incidence of G6PD deficiency in the populations of the Han and Li nationalities.In 367 individuals of Han population and 532 individuals of Li population in Hainan province , twenty-nine cases and forty-two cases were found respectively to be G6PD deficiency. The incidence of G6PD deficiency in the population of the Han and Li nationalities was 7.90% and 7.89% respectively.2. The analytic results by ARMS methodOf twenty-nine Han cases with G6PD deficiency, thirteen with G1376T(44.83%), three with G1388A(10.34%) and one with A95G(3.45%) were found. Among this mutations, one G1376T accompanying G1388A and one G1376T with A95G were identified. Three mutations of G6PD G1376T,G1388A and A95G accounted for 51.72% of G6PD deficiency in Han nationality. Of forty-two Li cases with G6PD deficiency, twenty-seven with G1376T(64.29%), ten with G1388A(23.81%) and three with A95G(7.14%) were found. Among this mutations, one G1376T accompanying G1388A and one G1376T with A95G were identified. Three mutations of G6PD G1376T, G1388A and A95G accounted for 90.48% of G6PD deficiency in Li nationality. The detected results indicated that eighteen cases (fourteen of Han nationality and four of Li nationality) with G6PD deficiency remained to be defined. 3. The sequencing results of eighteen samples without G1376T, G1388A and A95G mutations(1) One Han case was found to have a C to G substitution at cDNA nucleotide 612(C612G),which led to a GGC to GGG substitution of the 204th codon in G6PD. This mutation dosen't change the amino acid at 204 which is a glycine(Gly). therefore G6PD C612G is a silent mutation which has not been reported.(2) Two Han cases was identified to have a T to G substitution at cDNA nucleotide 855(T855G),which led to a CGT to CGG substitution of the 285th codon in G6PD. This mutation dosen't change the amino acid at 285 which is a arginine (Arg). therefore G6PD T855G is a silent mutation which has not been reported.(3) One Han case was found to have a single base of T deletion at nucleotide 636 or 637 in the 5th intron(IVS-5 636 or 637 T del) , which has already been described in Japanese. This mutation was first reported in China.(4) Three Han cases were found to be G6PD C1311T mutation , which led to a C to T substitution at cDNA nucleotide 1311 and caused a TAC to TAT substitution of the 437th codon in G6PD. G6PD Cl31 IT is a silent mutation. Meanwhile, the three cases with C1311T mutation were demonstrated to have a T to C substitution at nucleotide 93 in the 11th intron(IVS-ll T93C). This results showed that G6PD C1311T mutation strongly linkages with IVS-11...