Resumen

LUNA-NEVAREZ, Pablo et al. Identification of one polymorphism from the PAPP-A2 gene associated to fertility in Romosinuano beef heifers raised under a subtropical environment. Rev. mex. de cienc. pecuarias [online]. 2012, vol.3, n.2, pp.185-200. ISSN 2448-6698.

The objective was to identify single nucleotide polymorphisms (SNP) associated to fertility in cows raised under a subtropical environment. Re-sequencing of nine genes associated to GH-IGF endocrine pathway, which are located in bovine chromosomes 5, 16 and 20, identified 73 SNP useful for associative genetic studies; however, only seven resulted as polymorphic and unique to the Romosinuano breed. Then, DNA samples were extracted from 129 beef heifers and used to determine genotypes corresponding to each SNP. Mixed model analysis identified one SNP from the PAPP-A2 gene (C/T, rs110490898) as predictor (P<0.05) of reproductive performance. The allele T was the most favorable allele (P<0.05), because it was associated with lower age at first calving (-37.1 ± 14.4 d) and age at second calving (-65.43 ± 30.8 d). In the contrast analysis, the linear term resulted as significant and quadratic term as non significant, which suggested an additive effect of the alleles. These results provide evidence to support the PAPP-A2 gene as a candidate gene associated to reproductive performance in heifers and first-calf cows from the Romosinuano breed, raised under a subtropical environment.

Palabras llave : PAPPA2; Reproductive performance; Romosinuano; SNP.