Interaction between glucose-6-phosphate dehydrogenase deficiency and sickle cell gene in Saudi Arabia.

Sickle cell haemoglobin (Hb S) and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency occur at a variable prevalence in different regions of Saudi Arabia. The interaction between the two genes was investigated in 1859 Saudi males in different regions where the two genes were known to exist at both a high and a low frequency. The frequency of G-6-PD deficiency was the highest in the sickle cell anaemia (SS) cases. Furthermore, in all areas except Tehamat-Aseer (on the Red Sea), the frequency of G-6-PD deficiency was greater in the sickle cell heterozygotes (AS) than in the normal (AA) individuals. The interaction between G-6-PD deficiency and sickle cell gene in the homozygotes and heterozygotes may provide additional benefit against environmental and genetical factors, and may play a role in the amelioration of sickle cell disease in Saudis.