Genetic variation of the second exon of the ELA-DRB genes in Argentine Creole horses.

DIAZ, S.; GIOVAMBATTISTA,G.; DULOUT, F.N.; PERAL-GARCIA, P

ANIMAL GENETICS

Blackwell Publishing

Lugar: Schwerzenbach, Switzerland; Año: 2001 vol. 32 p. 257 - 263

0268-9146

Genetic variation in the equine leucocyte antigen-DRB (ELA-DRB) second exon wasinvestigated using polymerase chain reaction (PCR) amplification, restriction fragmentlength polymorphism (RFLP) of PCR products (PCR-RFLP) and deoxyribonucleic acid(DNA) sequencing. Eight distinct PCR-RFLP patterns could be identified in the studiedArgentine Creole (AC) horses. The number of observed patterns per individual rangedfrom four to six, thus con®rming the presence of multiple DRB copies in AC horses.Three PCR-RFLP alleles and three new sequences were identified. The estimated ratesof synonymous and non-synonymous substitutions among ELA-DRB exon 2 sequenceswere higher within the antigen recognition site (ABS) than on the non-ABS. Phylogeneticanalysis showed that the nucleotide sequences clustered in two main groups,while some sequences were not included in either group. Finally, the identification ofthe number of alleles per animal, the phylogenetic and segregation analyses allowed usto explain the number of ELA-DRB loci. However, it was not possible to identify specificalleles with specific loci.