Characterization of abnormalities in the γglobin gene arrangements of japanese newborns

Cord blood samples from 889 healthy Japanese newborns from three districts of Honshu Island were studied with the purpose of characterizing the γglobin genes in the Japanese. The A_γT gene frequency was 0.159 which is the same as that found elsewhere in Japan. The haplotype of the chromosome with the found elsewhere A_γT gene was [-+ + - + (+ or -) (+ or -)] at eight polymorphic sites. Data from analyses of DNA and the proportion of γ chains in Hb F showed the existence of various kinds of γglobin gene arrangements; six genotypes were observed for individuals with high G_γ values and triple or quadruple γglobin gene arrangements, and seven genotypes for babies with low G_γ values and a single γglobin gene. The in vivo expression of the γglobin gene located at the third or fourth position in the multiple gene arrangement was found to be about 5% and 2.5% of the total, respectively. The haplotype for the chromosomes with a triple γglobin gene was [+ - (-) - +], but that for the chromosomes with a single γglobin gene remains unclear. In addition, a new type of Bgl II polymorphism in the G_γ-globin gene was observed.