Sequence analysis of the human fucosyltransferase 1 and 2 genes in Tibetan blood donors: identification of three novel alleles

Abstract

The α(1,2)-fucosyltransferase gene 1 (FUT1) and 2 (FUT2), respectively, regulate H antigen synthesis in red blood cells and body fluids. Genetic polymorphisms of FUT1 and FUT2 are ethnically and geographically specific. Healthy unrelated Tibetan blood donors (n = 200) from the Tibet Autonomous Region of China were recruited for this study. The entire FUT1 and FUT2 coding regions were amplified and sequenced. The haplotypes including novel single-nucleotide polymorphisms (SNPs) were determined by clone sequencing. In Tibetans, the major FUT1 allele was wild-type allele with a frequency of 97.75%. One novel FUT1 allele was defined by a novel synonymous mutation (846T>G). The two most common FUT2 alleles were functional allele Se(357) with a frequency of 32.75% and nonfunctional allele se(357,385) with a frequency of 55%. Two new FUT2 alleles were found at low frequency. They were characterized by two novel SNPs on the basis of se(357,385) : 617 T>G (V206G) and 841 G>A (G281R). Three new alleles in FUT1 and FUT2 genes were identified in the study. The allelic polymorphisms of FUT1 and FUT2 in Tibetans show a population-specific manner.