Molecular characterisation of red cell glucose-6-phosphate dehydrogenase deficiency in Singapore Chinese.

Sixty-two G6PD deficient Chinese males have been investigated for the presence of seven mutations of the coding region of the G6PD gene by natural and artificially created amplified restriction sites. The results show that the G to T substitution at nucleotide (nt) 1376 and G to A substitution at nt 1388 represent 24% and 21% of G6PD deficiency, respectively, in the Singapore Chinese; 37% of the sample could not be characterised. The remaining samples were identified as follows: 10% C-->T at nt 563, 5% A-->G at nt 95, and 3% C-->T at nt 1024. The G to A substitution (nt 487) and the substitution A-->G (nt 493) were not present in this sample. None of the subjects with the Mediterranean mutation (563 C-->T) had the silent mutation at 1311 (C-->T). This study confirms the extreme molecular heterogeneity of the G6PD gene in the Chinese.