Distribution of Hemoglobin E and β-Thalassemia in Kampuchea (Cambodia)

The hemoglobin type of 360 adult Cambodian subjects was determined by cellulose acetate electrophoresis and microcolumn chromatography. The following distributions and frequencies of the Hb E (beta E) and the beta-thalassemia (beta-thal) genes were found: in a group of 264 Cambodians of rural areas 153 Hb A, 83 Hb AE, 19 Hb E, and nine beta-thalassemia minor (frequency beta E 0.2292, beta-thal 0.0170). In an urban group from the capital Phnom Penh there were 68 Hb A, 21 Hb AE, four Hb E, and three beta-thalassemia minor (frequency beta E 0.1510, beta-thal 0.0156). The low frequency of beta E in the urban group is probably due to Chinese admixture. Possible causes of the observed deficiency of Hb AE heterozygotes in comparison with Hardy-Weinberg equilibrium are discussed.