Frequency of Mi^a (MNS7) and Classification of Mi^a-Positive Hybrid Glycophorins in an Australian Blood Donor Population

MNS blood group system genes GYPA and GYPB share a high degree of sequence homology and gene structure. Homologous exchanges between GYPA and GYPB form hybrid genes encoding hybrid glycophorins GP(A-B-A) and GP(B-A-B). Over 20 hybrid glycophorins have been characterised. Each has a distinct phenotype defined by the profile of antigens expressed including Mi a . Seven hybrid glycophorins carry Mi a and have been reported in Caucasian and Asian population groups. In Australia, the population is diverse; however, the prevalence of hybrid glycophorins in the population has never been determined. The aims of this study were to determine the frequency of Mi a and to classify Mi a -positive hybrid glycophorins in an Australian blood donor population.