Relationships between %Hb F or %G gamma and the haplotypes in the beta-globin gene cluster in the normal adult Japanese and Korean populations.

Haplotypes or subhaplotypes in the beta-globin gene cluster were examined in 31 normal Japanese and 21 Korean families. Major haplotypes were VII, V, and I, which shared a common subhaplotype [+----], and occurred in 70% of the Japanese and 68% of the Koreans. Three haploypes which shared a common subhaplotype [-+-++], bearing the XmnI site 5' to the G gamma-globin gene, occurred in 13% of the Japanese and 7.3% of the Koreans. One subhaplotype [-++-+], which is closely linked to the A gamma T-globin gene, had an incidence of 6.6% in the Japanese and 20% in the Koreans. Rare subhaplotypes [---++], and [- +] which has been observed mainly in Melanesians and Polynesians, and a very rare subhaplotype [-----] were observed. The present study suggests that high or low G gamma-globin chain production is closely related to subhaplotypes [-+-++] and [+----], respectively, among the normal adult population.