| It has been demonstrated that two distinct a (l,2)-fucosyltransferases are present in human tissues. One is the //gene (FUT7) - encoded a (1,2) -fucosyltransferase (H enzyme) that regulates expression of ABH antigens in erythrocytes. The other is the Secretor gene (FUT2) - encoded secrelor type a (l,2)-fucosyltransferase (Se enzyme) that regulates expression and secretion of ABH antigens in the epithelial cell of glands and body fluids.After cloning the FUT2 gene by Kelly et al,molecular analyses of FUT2 indicated the non-function alleles (se) which were generated by single base mutation (G428A A385T C57IT C628T,G849A and C658T) caused Se enzyme deficient. The distribution of these alleles is region specific and race specific.In the present study,blood samples of 90 unrelated Han Chinese individuals from Shandong Province and 90 Mongols from Inner Mongolia were collected randomly and genomic DNA was extracted. According to the primers sequences,which were published by Kelly,a 1071-bp fragment containing the enzyme coding region of FUT2 gene was amplified by PCR. The products were used in RFLP analysis. We found the G849A nonsense mutation that was responsible for the Se enzyme inactivation in Shandong Han Chinese and Mongolian of Inner Mongolia individuals was in the same frequency,0.55%. We did not find the C57 1T C628T.. C658T or A375G point mutations in both populations. We summed up and analyzed the polymorphisms of the FUT2 gene of three groups in the world with references to other published data. Further discussion was made for the hypotheses of origin and generation of special point mutations of FUT2 gene.Master Candidate:Zhang Ying Major:Microbiology and Immunology Supervisor:prof. Xuan Shiwei prof. Wang Li prof. Jin Feng... |
