Resumen de Medidas de consangunidad al viejo y nuevo estilo

M.C. Rodriguez, A.I. Fernández, C. Barragán, L. Silió López

• Traditional inbreeding measures have been calculated using pedigree information. However, when genealogy is not available, several alternative inbreeding metrics based on multiple markers have been proposed. The emergence of the high throughput SNP genotyping platforms reinforces this option, although its usefulness depends on the genealogical inbreeding dispersion. In the present analysis of inbreeding of 217 Iberian sows of the Torbiscal strain, we have calculated old and new SNP-derived inbreeding metrics from the pedigree (FPED), the homozygosity of 26,646 typed SNPs (FMOL) and runs of homozigosity (FROH) identified in the same genotypes. Although the results showed a moderate correlation between FPED and FMOL (0.679), similar inbreeding rates per generation and effective population sizes were estimated from pedigree and molecular metrics. A slighty greater correlation between FPED and FROH (0.685) was observed. The detailed examination of ROH sizes showed a higher proportion of medium and large ROHs in the most inbred animals. Besides, the distributions across chromosome positions of ROHs grouped by size confirmed the negative effect on the ROH size of the high recombination rates in the telomeres. The pattern of these distributions in this Iberian pig strain is intermediate between those of European wild boars and of strongly selected domestic breeds.