Glucos 6-phosphate dehydrogenase deficiency in Tehran, Zanjan and Sistan-Balouchestan provinces: prevalence and frequency of Mediterranean variant of G6PD

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an enzymopathy affecting about 400 million people worldwide. The distribution of G6PD deficiency and the molecular genetics of this enzyme vary widely among different ethnic groups. The aim of this study was to find out the frequency of G6PD deficiency and characterize the Mediterranean type mutationin deficient individuals in Turk, Balouch and Fars ethnic groups in Zanjan, Iranshahr and Tehran provinces. 1500 unrelated male individuals from Zanjan and 305 unrelated male students from Iranshahr were screened for G6PD deficiency by fluorescent spot test. Genomic DNA was extracted from deficient individuals and also from 64 G6PD deficient individuals from Tehran city. PCR was used to amplify flanking regions of exons 6 and 7 of this gene. The PCR products were digested by the MboII enzyme and electrophoresed on 3% agarose gel. Thirty-three (2.2%) individuals were shown to be deficient for G6PD from Zanjan population. Twenty-four out of 33 (72.8%) of the deficient individuals showed a mutation at nt 563 which is characteristic of Mediterranean type of mutation. Nine individuals were negative for this mutation. Fifty nine (19.3%) individuals of Iranshahr were shown to be deficient for G6PD. At the molecular level, 50 (85%) of the individuals showed Mediterranean type of mutation and 15% were negative for this mutation. Our results from Tehran showed that 47/64 (73.4%) of deficient individuals had Mediterranean type mutation and 26.6% were negative for this mutation. Despite different frequencies exist for deficiency of G6PD in Turk, Balouch and Fars populations, the results of the present study and others have shown that the predominant mutation of G6PD in Iran is of Mediterranean type.