Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human enzyme deficiencies. More than 130 different molecular abnormalities have been described worldwide, with considerable variation in the enzyme among various racial groups. Data from Kuwaiti populations are scarce, and the studies available are the result of screening male blood donors who may not be truly representative of the Kuwaiti population.
The objective of this study was to investigate the mutation spectrum of the G6PD gene among Kuwaiti Arabs.
DNA was extracted from 82 G6PD-deficient Kuwaiti subjects (75 men and 7 women) and screened for gene mutations using polymerase chain reaction/restriction fragment length polymorphism and polymerase chain reaction/single-strand conformation polymorphism followed by direct sequencing. A total of 1209 randomly selected Kuwaiti adult subjects of both sexes were then screened for any characterized mutation.
G6PD Mediterranean(563C-->T), and A-(202G-->A,376A-->G) genotypes were characterized as the most common variants among the G6PD-deficient population, representing 0.742 and 0.124 allele frequencies, respectively. The 2 previously described mutations, G6PD Chatham(1003G-->A) and Aures(143T-->C), were found at lower frequencies (0.101 and 0.034, respectively). The allele frequencies for these 4 G6PD variants among the randomly selected Kuwaitis were 0.035, 0.0074, 0.0046, and 0.0023 for Mediterranean, A-, Chatham, and Aures, respectively.
This study has characterized the molecular heterogeneity of G6PD variants among ethnic Kuwaitis. The findings suggest that gene flow from the Indian subcontinent, sub-Saharan African, and other parts of the Mediterranean may have contributed to the observed G6PD mutations seen in the Kuwaiti population.