DRA encodes the alpha chain of the DR heterodimer, is closely linked to DRB and is considered almost monomorphic in major histocompatibility complex region. In this study, we identified the exon 2 of DRA to evaluate the immunogenetic diversity of Chinese south indigenous goat. Two single nucleotide polymorphisms in an untranslated region and one synonymous substitution in coding region were identified. These data suggest that high immunodiversity in native Chinese population.
Major histocompatibility complex
Major histocompatibility complex (MHC) class II genes play important recognition roles in the immune system in vertebrates. We cloned the MHC class II genes A and B in the stone flounder (Kareius bicoloratus). The full-length cDNA and DNA sequences of both genes were obtained, and their characteristic motifs were analyzed. The DNA sequence of stone flounder MHC class II A consists of four exons, while gene B contains six exons. The extra intron in gene B might be a common feature in most of its Acanthopterygii orthologs.
Major histocompatibility complex (MHC) genes play an important role in the immune response of vertebrates. Allelic polymorphism and evolutionary mechanism of MHC genes have been investigated in many mammals, but much less is known in teleosts. We examined the polymorphism, gene duplication and balancing selection of the MHC class II DAB gene of the half-smooth tongue sole (Cynoglossus semilaevis); 23 alleles were found in this species. Gene duplication manifested as three to six distinct sequences at each domain in the same individuals.
TAP1 and TAP2 genes code for the two subunits of the transporter associated with antigen processing (TAP), and in chicken they are located between the two MHC class I genes. Using primers based on chicken sequences, the genomic regions corresponding to chicken TAP1 exons 6 to 7 and TAP2 exons 4 to 6 (which encode portions of the chicken TAP1 and TAP2 molecules corresponding to the human peptide-binding regions) were amplified and sequenced from chicken (70 birds), turkey (24), pheasant (6), and guinea fowl (7).