New DNA polymorphisms define ethnically distinct haplotypes in the human transferrin receptor gene

In a study of transferrin receptor (TFR) polymorphism in different ethnic groups using PCR and restriction cleavage we found a new Hin6I polymorphism in intron 7 and confirmed a tentative BanI polymorphism in exon 4 reported by Evans and Kemp [Gene 1997;199:123-131], In all ethnic groups there was a complete and highly significant (p < 10(-10)) linkage disequilibrium where all BanI 1 alleles were linked to Hin6I 1 alleles, Furthermore in the European populations, but not in the Chinese, there was a close correlation between the three BanI-Hin6I haplotypes and the alleles of a previously described three-allelic RsaI polymorphism in the TFR gene studied by Southern blotting, There were distinct ethnic differences in TFR allele and haplotype frequencies, Thus the Saamis were significantly different from the other European ethnic groups, and the Lithuanians had a significantly increased frequency of the BanI 2-Hin6I 1 haplotype, suggesting that this marker may be informative in tracing prehistoric migrations and admixture by Baltic peoples, The new TFR polymorphisms and haplotypes may also be useful markers in studies of interactions with the transferrin and hemochromatosis genes, the genetic influence on body iron stores and disease associations.