Systematic sequence analysis of the human fucosyltransferase 2 (FUT2) gene identifies novel sequence variations and alleles

BACKGROUND: The FUT2 gene regulates the expression of ABH antigens in body secretions and hence controls the secretor status. It is highly polymorphic. STUDY DESIGN AND METHODS: Healthy Chinese (n = 79) and Caucasian (n = 20) subjects were recruited for this study. Lewis blood group and secretor status were determined. The entire FUT2 coding region was amplified and screened for sequence variations by single-strand conformation polymorphism analysis under four different conditions to ensure comprehensive detection, and representative samples with distinct banding patterns were characterized by DNA sequencing. The haplotypes of novel alleles were determined by sequencing of cloned inserts. RESULTS: Seventeen single-nucleotide polymorphisms and one 3-base duplicating insertion were identified. Six novel FUT2 alleles each found in a heterozygous individual were defined by six novel sequence variations: 21 0A > G (T70T), 380G > A (R127H), 572G > A (R191Q), 748_750dupGTG (V250dup), 853G > A (A285T), and 855A > C (A285A). The three most common alleles were Se, Se-367,Se-385 and se(482), Se-357, and Se in Chinese persons (total frequency, 94%) and se(428), Se-357 and Se in Caucasian persons (total frequency, 85%). The FUT2 genotypes correlated with Lewis phenotypes and secretor status. CONCLUSION: This study identified 18 sequence variations in the FUT2 gene, and 6 were novel. The frequencies of alleles and genotypes were also determined in Chinese and Caucasian persons.