RESUMO
BACKGROUND: The Lewis and secretor gene determine the Lewis phenoytpe. Conventional Lewis blood grouping is difficult because of the presence of nongenuine Lewis negative individuals. Recently, the Lewis gene (FUT3), the secretor gene (FUT2), and several mutations that cause the Lewis negative and the nonsecretor phenotypes were identified. The purpose of this study was to compare Lewis phenotypes determined by commercially available three pairs of monoclonal antibodies with the Lewis and secretor genotypes. METHODS: RBCs for phenotyping and peripheral blood leukocytes for genotyping of FUT3 and FUT2 gene were obtained from 184 apparently healthy volunteers. Lewis phenotypes were determined on K3EDTA-stablized fresh blood samples using three pairs of commercially available monoclonal antibodies, one of which was the column agglutination method and the others were the tube agglutination methods. Lewis blood group genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to detect T59G, G428A, C357T, and A385T mutations. RESULTS: The frequencies of the Lewis blood group phenotype were Le(a+b-) 15.0%, Le(a-b+) 65.8%, Le(a-b-) 14.8%, and Le(a+b+) 4.3%, respectively. The Lewis blood group phenotypes determined by three pairs of monoclonal antibodies were 93.5%, 93.5% and 89.1% in accordance with the genotypes. The frequencies of Le, le, Se and se alleles were 64.4%, 35.6%, 48.6%, and 51.4% and we have newly detected 4 cases with only one A385T mutation. All of the Le(a+b+) phenotype cases have both C357T, and A385T homozygotic mutations. CONCLUSIONS: The PCR method may be effectively used for the genotyping of the FUT3 and FUT2 genes and offers an attractive alternative to Lewis phenotyping using hemagglutination method.