Molecular characterisation of red cell glucose-6-phosphate dehydrogenase deficiency in north-west Pakistan.

233 Pushtoons (129 males and 104 females), 51 Punjabi Muslims (29 males and 22 females) and 21 Afghans (15 males and 6 females) were screened for the presence of red cell glucose-6-phosphate dehydrogenase (G6PD) variants by a dye decolouration screening test and starch gel electrophoresis. The overall frequency of G6PD deficiency in males was found to be about 10%. 17 male G6PD-deficient samples were further investigated for the C-->T substitution at nucleotide (nt) 563 (the Mediterranean mutation) and the C-->T substitution at nt 1311 (the 'silent' allele) of the G6PD gene by PCR amplification followed by digestion with appropriate restriction enzymes. 10 of the 13 Pushtoon, 2 Punjabi and 1 Afghan males had the 563 mutations. Only 1 (Punjabi) out of 13 G6PD-deficient males with the 563 mutation had the silent mutation at nt 1311. The frequency of the silent mutation was found to be about 0.20 in the 60 Pushtoon and 19 Punjabi non-deficient males.