Polymorphism of human CD1a, CD1d, and CD1e in exon 2 in Chinese Han and She ethnic populations.

CD1 molecules are the major histocompatibility complex (MHC)-like glycoproteins specialized in capturing and presenting a variety of glycolipid to antigen-specific T-cells. There are five closely linked CD1 genes termed as CD1a, CD1b, CD1c, CD1d, and CD1e. CD1 gene features limited the polymorphism in exon 2 which encodes for the alpha1 domain. Few investigations on the allele frequencies of the CD1 genes have been reported to date; however, variation of CD1 allele frequency in different ethnics has been observed. In the current study, the CD1a, CD1d, and CD1e gene polymorphisms in exon 2 (alleles 01 and 02) in a group of normal Chinese Han and She individuals were analyzed. Similar allele prevalence was observed between the two populations. The CD1e allele frequency was 37.1% (allele 01); 62.9% (allele 02) and 39.3% (allele 01); 60.7% (allele 02) for Han and She populations, respectively. CD1e was the only polymorphic gene with a genotype frequency for Chinese Han (01/01, 11.0%; 01/02, 52.2%; 02/02, 36.8%) and She (01/01, 13.2%; 01/02, 52.1%; 02/02, 34.7%) individuals, respectively. No CD1a allele 01 and CD1d allele 02 were observed in either population. Our findings indicate that the polymorphism of CD1a, CD1d, and CD1e genes in exon 2 is very limited in the Chinese Han and She ethnics.