Molecular Genetics of the ABO Histo‐Blood Group System

Abstract
Molecular genetic study of the histo-blood group ABO system has elucidated the allelic basis of this genetic locus. Comparison of the nucleotide sequence has identified in the coding region differences which change amino acid sequences of the glycosyltransferases coded by these genes. Effects of the differences (mutations) on the specificity and activity of the glycosyltransferases have been examined.