Null Genetic Differentiation among Flocks Contributing to the Ripollesa Sheep Herdboob

Abstract Text:

Several subpopulations were previously described in the Ripollesa sheep breed on a phenotypic basis, and this research focuses on the identification of the subsequent underlying genetic structure, if any. A total of 269 males and 2,366 females from 13 purebred Ripollesa flocks were genotyped for 49 SNP. Genetic differentiation across flocks was evaluated by computing both D_est and F_ST parameters across loci. It is important to highlight that  D_est provided higher estimates, although they were remarkably small in all pairwise comparisons. On average, D_est was 0.017 ± 0.001, whereas the other genetic differentiation parameter, F_ST, evidenced the same behavior with even smaller (and non-significant) estimates; they suggested the absence of genetic structure in the Ripollesa sheep breed. These results suggested that phenotypic differences between flocks must be mostly due to environmental factors or a few major genes (e.g., horn inheritance).

Keywords:

differentiation

genetic variability

Ripollesa breed

SNP