GLUCOSE-6-PHOSPHATE-DEHYDROGENASE DEFICIENCY AND SICKLE-CELL GENES INBISHA

This study was conducted on 820 Saudi males and females from Bisha in the western province of Saudi Arabia, Blood samples were analysed to d etermine the frequency of glucose-S-phosphate dehydrogenase deficiency and haemoglobin S (Hb S) genes, and to investigate interactions betwe en the two genes. Severe G-6-PD deficiency in this population was due to G-6-PD-Mediterranean; the African variant G-6-PD-A(-) was not detec ted. The normal and common form of the enzyme was G-6-PD-B+, occurring at a frequency of 0.8444 and 0.8177 in males and females, respectivel y. Variants included G-6-PD-A(+), G-6-PD-Mediterranean, and G-6-PD-Med iterranean-like at frequencies of 0.0043, 0.0767, and 0.0746, respecti vely, in males and 0.0057, 0.05413, and 0.0855, respectively, in femal es. Sickle cell haemoglobin (Hb S) was encountered in the homozygous ( 4 per cent) and heterozygous (10 per cent) states at a gene frequency of 0.0860. No interaction between G-6-PD deficiency and Hb S gene was observed. A severe haematological and clinical presentation of the Hb SS disease was encountered in the children from Bisha.