Large cohort screening of G6PD deficiency and the mutational spectrum in the Dongguan District in Southern China

Abstract

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzymatic disorder of the erythrocytes that affects 400 million people worldwide. We developed a PCR-reverse dot blot (RDB) assay to screen twenty genotypes of seventeen Chinese G6PD mutations and investigate the spectrum of G6PD deficiency mutations in Dongguan District, Guangdong Province, in southern China.

Method: The PCR-RDB assay consists of multiplex PCR amplification of seven fragments in the G6PD target sequence of wild-type and mutant genomic DNA samples followed by hybridization to a test strip containing allele-specific oligonucleotide probes. A total of 16,464 individuals were analyzed by a combination of phenotypic screening and genotypic detection using the PCR-RDB assay and DNA sequence analysis.

Results: The PCR-RDB assay had a detection rate of 98.1%, which was validated by direct sequencing in a blind study with 100% concordance. The G6PD deficiency incidence rate in Dongguan District is 4.08%. Thirty-two genotypes from 469 individuals were found. The two most common variants were c.1376G>T and c.1388G>A, followed by c.95A>G, c.871G>A, c.392G>T, and c.1024 C>T. In addition, two rare mutations (c.703C>A and c.406C>T) were detected by DNA sequencing analysis. In our study, 65 cases harbored the C1311T/IVS polymorphism and 67 cases were homozygote.

Conclusion: The PCR-RDB assay we established is a reliable and effective method for screening G6PD mutations in the Chinese population. Data on the spectrum of mutations in the Dongguan District is beneficial to the clinical diagnosis and prevention of G6PD deficiency.

Fig 1. Layout of the probes’ dotting in the nylon strip designed for the reverse dot blot assay.

N denotes the wild-type probes corresponding to each mutant probes (denoted at each mutation).

Fig 2. Representative genotyping results of G6PD deficiency using reverse dot blot assay.

(1)c.1376 G>T heterozygotes;(2) c.1388 G>A heterozygotes; (3)c.487 G>A Hemizygote; (4)c.95 A>G heterozygotes; (5)c.392 G>T heterozygotes; (6)c.871 G>A heterozygotes; (7)c.1381 G>A Hemizygote; (8)c.1387 C>A Hemizygote; (9)c.493 A>G Hemizygote; (10)c.592 C>T Hemizygote; (11)c.1004 C>T Hemizygote; (12)c.1004 C>A Hemizygote; (13)c.1024 G>T heterozygotes; (14)c.517 T>C Hemizygote; (15)c.519 C>G Hemizygote; (16)c.519 C>T Hemizygote; (17)c.835 A>G Hemizygote; (18)c.835 A>T Hemizygote; (19)c.1311 C>T Hemizygote; (20)c.1360 C>T Hemizygote. (21)c.1376 G>T/c.1388 G>A double heter-ozygotes (22) normal control.