The Interaction of α-Thalassaemia and Haemoglobin G Philadelphia

Abstract

An American Negro woman was found to have HbH disease in association with HbG Philadelphia (.alpha.68-asn .fwdarw. lys). Starch gel electrophoresis failed to reveal the presence of any HbA or HbA2 and studies of globin chain synthesis indicated absence of .alpha.A production. The .alpha.G/.beta. synthesis ratio was 0.63. The woman''s son and her 2 half-sibs had .alpha.-thalassemia trait when no HbH and .alpha./.beta. synthesis ratios of 0.84, 0.84 and 0.76. There is apparently no functioning .alpha.A gene linked to the .alpha.G gene. The absence of .alpha.A synthesis by the propositus also indicates that the .alpha.-thalassemia gene trans to the .alpha.G gene completely suppresses .alpha. chain production, the 1st evidence for such a gene in Negroes.