title: A comparison of the beta A-and beta B-globin gene clusters of sheep.
abstract: Domestic sheep have two common alleles at the adult beta-globin locus, beta A and beta B. Here we report the structure of the beta-globin locus of A-haplotype sheep. The locus consists of 12 genes, organized as a triplicated 4-gene set: 5' epsilon 1-epsilon II-psi beta I-beta C-epsilon III-epsilon IV-psi beta II-beta A-epsilon V-epsilon VI-psi beta III-beta F 3'. This arrangement is identical to that of the closely related goat locus. Sheep with the B haplotype have a locus arrangement consisting of a duplicated four-gene set, lacking the beta C gene as well as three other genes present in A sheep and goats. In order to understand the evolutionary history of the B sheep locus, we have sequenced the beta B gene from these sheep, and the beta C gene from A-haplotype sheep, and compared the sequences to those of the sheep beta A, goat beta C, and beta A, and cow adult beta genes. Our results indicate that the beta B gene has diverged recently from the beta A gene, and therefore the beta B locus structure may have resulted from a recent deletion from a triplicated locus.
authors.affiliation: Department of Microbiology and Molecular Genetics, University of Cincinnati, Ohio 45267.
authors.forename: K J
authors.initials: KJ
authors.lastname: Garner
authors.forename: J B
authors.initials: JB
authors.lastname: Lingrel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics; D003001:Cloning, Molecular; D008040:Genetic Linkage; D005914:Globins / Q000235:genetics*; D006041:Goats / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D015183:Restriction Mapping; D012756:Sheep / Q000235:genetics*
chemical_list: D005914:Globins