Molecular analysis of plasma alpha 1.3-fucosyltransferase deficiency and development of the methods for its genotyping

Four patients with mental illness were found to be deficient in plasma alph a1,3-fucosyltransferase for the first time in Japan [Exp Clin Immunogenet 1 999;16:125-130]. Complete sequencing of FUT6 genes in these individuals rev ealed the presence of two point mutations, i.e., G739 to A (Glu-->247 to Ly s) and C945 to A (Tyr-->315 to stop). In addition to two reported alleles h aving G739 to A (pf1) and G739 to A and C945 to A (pf3), a new mutated alle le having C945 to A (pf2) was found to be present and all the individuals w ho lack alpha1,3-fucosyltransferase activity in plasma were found to posses s pf genes homozygously (pf/pf). In order to detect such lethal mutations i n FUT6 genes easily, PCR-RFLP methods have also been developed and applied for the screening of FUT6 deficiency in a large number of samples which res ulted in the demonstration of three additional fUT6-deficient individuals. The absence of alpha1,3-fucosylated molecules on alpha (1)-acid glycoprotei n in plasma from all the 7 individuals was confirmed to result from the pla sma alpha1,3-fucosyltransferase deficiency. Copyright (C) 2001 S. Karger AG . Basel.