Allele mining in grape for the analysis of complex traits
Résumé
In the past decade, thanks to an important international effort, our understanding of grape nuclear diversity greatly improved, in particular through European Programs such as GenRes81 and GrapeGen06 leading to the standardization of SSR analysis. Our knowledge of grape diversity in genes, is however still limited. A precise knowledge of gene diversity will be highly beneficial in order to improve our understanding of quantitative important traits. Since the publication of the grape sequence, we have now the possibility to study gene diversity in grape at a large scale. In the present work, SSR diversity in the INRA grape collection (2300 cultivars) enabled the definition of a highly diverse sample of 27 V. vinifera accessions. This set was completed by 7 accessions of V. vinifera subsp. sylvestris and several accessions of Vitis species from Asia or America. Analysis of gene diversity over this sample of 47 accessions was thus performed for a set of 900 genes scattered through the grape genome. Through bioinformatics developments, diversity maps of the grape genome have been drawn at different levels. This data will be very useful in order to select markers for mapping, for comparison of diversity between Vitis species and for the search of selective sweeps in grape. It will also be very useful in the assessment of DL in grape, a prerequisite for Whole Genome Association studies.