Unequal crossing-over: a common basis of single alpha-globin genes in Asians and American blacks with hemoglobin-H disease

Abstract

The α-globin genes of five black Americans, two Chinese, and five Filipinos with HbH disease (an α-thalassemia state in which there is a single functional α gene) were analyzed by restriction endonuclease techniques. All subjects were found to have one chromosome 16, lacking both α genes, and another containing a single α gene ( –/-α). Restriction endonuclease patterns of the DNA obtained from all 12 subjects were identical and compatible with unequal crossing-over as the mechanism of origin of the single α gene in these individuals.