Adult chicken alpha-globin genes alpha A and alpha D: no anemic shock alpha-globin exists in domestic chickens.

Abstract

Three .alpha.-type globin genes were identified in the .alpha.-globin linkage group of chickens. No other .alpha.-type genes were directly shown to be within 10 kilobase pairs of any of these 3 closely linked genes. These 3 genes were conclusively identified by DNA sequence analysis. The gene at the 5'' end of the linkage group is an embryonic .alpha.-type globin gene, .pi. or .pi.'', and the central gene corresponds to the minor adult .alpha.-globin, .alpha.D. The 3''-terminal gene sequence corresponds to the sequence of c[complementary]DNA clones previously described as .alpha.S, a presumed anemic shock-induced .alpha.-globin gene. Several groups of workers have isolated .alpha.S-type cDNA clones but no one has identified as cDNA clone corresponding to the published amino acid sequence of the major chicken .alpha.-globin, .alpha.A. The .alpha.S-type sequence was identified as the only abundant .alpha.-like globin sequence in cDNA clones made from reticulocyte mRNA isolated from nonanemic chickens. The .alpha.S-type sequence may correspond to the true .alpha.A-globin species.