Disease relevance of DLA-DRB1

• To determine whether canine rheumatoid arthritis (CRA) is associated with dog MHC (DLA-DRB1) alleles which contain the QRRAA/RKRAA conserved third hypervariable region (3HVR) sequence, DNA samples were extracted from 61 dogs with clinically diagnosed small-joint polyarthritis and from 425 controls [1].

High impact information on DLA-DRB1

• Sequence-based typing (SBT) of the hypervariable region of DLA-DRB1, -DQA1 and -DQB1 alleles was used to determine genetic diversity [2].
• Three dog-leucocyte antigen (DLA) genes, DLA-DRB1, DQA1 and DQB1, were characterized by sequence-based typing and assigned to haplotypes for each dog [3].
• We applied SBT for the canine class I (DLA-88) and class II (DLA-DRB1) genes in beagle families prior stem cell transplantation [4].
• DLA class II allelic diversity was broad across breeds; 31/61 published DLA-DRB1 alleles, 11/18 published DLA-DQA1 alleles and 31/47 published DLA-DQB1 alleles were found among the 25 breeds [5].
• DLA-DRB1 genotype was significantly associated with levels of anti- Leishmania IgG and parasite status assessed by PCR [6].

Biological context of DLA-DRB1

• To date, DNA sequences for 29 dog DLA-DRB1 alleles have been reported [7].
• Within this data set, 58 different DLA-DRB1/DQA1/DQB1 three-locus haplotypes were identified, which were all found in at least two different animals [8].
• DLA-DRB1 genotypes were identified using molecular typing methods [1].
• DLA-DRB1 and DLA-DQB1 histocompatibility typing by PCR-SSCP and sequencing [9].
• Homozygosity or heterozygosity of each of two microsatellite markers, FH 2200 and FH 2202, located in the class I or class II region, respectively, did not correlate with homozygosity or heterozygosity of the most polymorphic known class I (DLA-88) or class II (DLA-DRB1) genes [10].

Anatomical context of DLA-DRB1

• Analyses of the nucleotide sequences and of the serological and cellular typing data revealed that phenotypic homozygosity, as defined by the DLA-D type in mixed leukocyte culture (MLC), tended to correlate with homozygosity at the DLA-DRB1 locus but not necessarily at the DLA-DQB1 locus [10].

Associations of DLA-DRB1 with chemical compounds

• In the class II region there is one complete DRB gene called DLA-DRB1 with at least 24 alleles and one full-length DQB gene, DLA-DQB1, with 20 alleles characterized to date [11].

Other interactions of DLA-DRB1

• Although 36 DLA-DRB1 and 10 DLA-DQA1 allele sequences have been published to date, no data on individual allele frequencies exists, either for specific breeds or cross breeds, and the full extent of the polymorphism at each of these loci is still not known [12].

References