Genomic hybridization of bovine class II major histocompatibility genes: 1. Extensive polymorphism of DQα and DQβ genes

Abstract

Class I1 genes of the bovine major histocompatibility complex (MHC) were investigated by Southern blot analysis using human cDNA probes for D Q a , DQP, D R a and DRP. The presence of a DQ-like and a DR-like subregion in cattle was clearly indicated. Highly polymorphic restriction fragment patterns were obtained when genomic DNA, digested with any one of the BamH1, EcoRI or PvuII restriction enzymes, was hybridized with the D Q a and the DQP probe. The polymorphisms were interpreted genetically by analysing five paternal half-sib families of the Swedish Red and White breed. The material comprised, besides the bulls, 28 offspring and their dams. The analysis resolved 9 and 12 allelic variants of D Q a and D O @ respectively. Thus, this investigation establishes a method for routine typing of MHC class I1 gene polymorphism in cattle. The results were entirely consistent with close linkage of DQa and DQP since no recombinant was found and since alleles at these loci occurred in complete linkage disequilibrium in the material investigated. Close linkage between D Q and the blood group locus M , which has previously been found to be closely linked to the serologically defined B O L A -A locus, was also indicated. In this study DNA was isolated from frozen semen samples of dead bulls, which shows that this type of analysis will be useful in genetic investigations in cattle breeds, where artificial insemination is practised.K~ywordst cattle, genetic polymorphism, RFLP, major histocompatibility complex, Southern blot analysis. lntroductionThe major histocompatibility complex (MHC) of vertebrates includes class I and class I1 genes which encode cell-surface proteins with a central function in the immune system (Klein 1975;Zinkernagel & Doherty 1979;Nagy et al.

Sequencing of 15 new BoLA‐DRB3 alleles

“…The DQ genes are duplicated and the number of DQA and DQB genes varies between haplotypes (Andersson & Rask, 1988). The DR region is composed of one DRA gene and at least three DRB loci (Andersson et al ., 1986a,b; Davies et al ., 1997). Exon2 of DRB 3 gene, in particular, has been the most widely studied class II gene as it is extremely polymorphic (Sigurdardottir et al ., 1988, 1991; van Eijk et al ., 1992; Gelhaus et al ., 1995; Sitte et al ., 1995).…”

The Major Histocompatibility Complex in Bovines: A Review

“…The class II DQ genes of the bovine major histocompatibility complex were investigated by Andersson et al [74, 75] using human cDNA probes for DQ alpha, DQ beta, DR alpha, and DR beta. The analysis resolved 9 and 12 allelic variants of DQ alpha and DQ beta, respectively.…”

Identification of genetic variations of exon 2 of BoLA‐DQB gene in five Chinese yellow cattle breeds

“…The number of DQA and DQB genes varies between haplotypes (Andersson & Rask, 1988). In these genes, DRB 3, DQA and DQB genes are high polymorphic (Andersson et al ., 1986a,b; Burke et al ., 1991; Davies et al ., 1994). Studies on variation of BoLA have been carried out for many years, and so far more than 40 alleles of BoLA‐DQB and 80 alleles of BoLA‐DRB 3 have been described (http://www.ebi.ac.uk/ipd/mhc/bola/).…”