title: Evidence supporting a single origin of the beta(C)-globin gene in blacks.
abstract: In order to characterize the origin(s) of the beta C-globin gene in blacks, 25 chromosomes bearing this gene were characterized at eight polymorphic restriction sites within the beta-globin gene cluster. Twenty-two of the 25 chromosomes were identical at all sites and possessed a haplotype seen only infrequently among beta A-bearing chromosomes in black Americans. Two different haplotypes were observed among the three exceptional chromosomes. These haplotypes were identical to the most common beta C allele in the 3' end of the beta-globin gene cluster, but differed in the 5' region. Partial haplotype analysis on an additional 14 beta C alleles demonstrated complete association with the typical beta C-associated polymorphisms in the 3' region of the cluster. These data can be most easily explained by a single origin of the mutation followed by spread of the mutation to other haplotypes through meiotic recombination 5' to the beta-globin gene.
authors.affiliation: Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Boehm
authors.forename: C E
authors.initials: CE
authors.lastname: Dowling
authors.forename: S E
authors.initials: SE
authors.lastname: Antonarakis
authors.forename: G R
authors.initials: GR
authors.lastname: Honig
authors.forename: H H
authors.initials: HH
authors.lastname: Kazazian
mesh_terms: D044383:Black People / Q000235:genetics*; D005914:Globins / Q000235:genetics*; D006239:Haplotypes; D006801:Humans; D005810:Multigene Family; D009154:Mutation; D012150:Polymorphism, Restriction Fragment Length; D001741:Black or African American
chemical_list: D005914:Globins