Glucose-6-phosphate dehydrogenase isozymes in Jordan Valley

The mean levels of glucose-6-phosphate dehydrogenase (G-6-PD), its deficiency prevalence, and its isozyme type distribution were estimated and compared in five-to-ten-year-old normal school children in two populations of Jordan: the North Jordan Valley (90% black) and Irbid (not black). The prevalences of G-6-PD deficiency in North Jordan and Irbid were 5.5% and 4.62% respectively, and were statistically not different (P>0.05). However, the mean levels of G-6-PD in North Jordan Valley and Irbid were 119.4 IU/10(9) RBC and 128.4 IU/10(9) RBC respectively, and were statistically different (P<0.05). The distribution of G-6-PD isozyme type A (the African types) and type B in North Jordan Valley were 21.5% and 78.5% respectively, and the corresponding rates in Irbid were 5.4% for type A and 94.6% for type B. There was an association between the isozyme type and the region (P<0.05). The high prevalence of the African type of G-6-PD isozyme in Jordan is discussed.