Improving Short- and Long-Term Genetic Gain by Accounting for Within-Family Variance in Optimal Cross-Selection

Antoine Allier (1, 2) , Christina Lehermeier (2) , Alain Charcosset (1) , Laurence Moreau (1) , Simon Teyssèdre (2)

1 GQE-Le Moulon - Génétique Quantitative et Evolution - Le Moulon (Génétique Végétale)
2 RAGT 2N

The implementation of genomic selection in recurrent breeding programs raises the concern that a higher inbreeding rate could compromise the long-term genetic gain. An optimized mating strategy that maximizes the performance in progeny and maintains diversity for long-term genetic gain is therefore essential. The optimal cross-selection approach aims at identifying the optimal set of crosses that maximizes the expected genetic value in the progeny under a constraint on genetic diversity in the progeny. Optimal cross-selection usually does not account for within-family selection, i.e., the fact that only a selected fraction of each family is used as parents of the next generation. In this study, we consider within-family variance accounting for linkage disequilibrium between quantitative trait loci to predict the expected mean performance and the expected genetic diversity in the selected progeny of a set of crosses. These predictions rely on the usefulness criterion parental contribution (UCPC) method. We compared UCPC-based optimal cross-selection and the optimal cross-selection approach in a long-term simulated recurrent genomic selection breeding program considering overlapping generations. UCPC-based optimal cross-selection proved to be more efficient to convert the genetic diversity into short-and long-term genetic gains than optimal cross-selection. We also showed that, using the UCPC-based optimal cross-selection, the long-term genetic gain can be increased with only a limited reduction of the short-term commercial genetic gain.

Mots clés: genomic prediction; optimal cross-selection; usefulness criterion; parental contributions; genetic diversity; Bulmer effect

Domaines: Génétique

Antoine Allier, Christina Lehermeier, Alain Charcosset, Laurence Moreau, Simon Teyssèdre. Improving Short- and Long-Term Genetic Gain by Accounting for Within-Family Variance in Optimal Cross-Selection. Frontiers in Genetics, 2019, 10, ⟨10.3389/fgene.2019.01006⟩. ⟨hal-03111538⟩