SNPS DEVELOPMENT IN WINEGRAPE: TOWARDS A FUNCTIONAL MAP

¹ Istituto Agrario San Michele All'adige Via Mach 1, 38010 San Michele All'Adige, Trento, Italy
² Max Planck Institut Fuer Zuechtungforschung Carl-von-Linne-Weg 10, 50829 Koeln, Germany

The grape genome is relatively small, ca. 475 Mbp, if compared with other largely studied crops. In spite of that relatively few is known about grape genetics. The most advanced tools of molecular biology could help to fill in such a gap. Undoubtedly, SNPs (single nucleotide polymorphisms) represent one of the most powerful tools for analysis of genomes, as proved in human research. In horticulture, no much has been done in this direction, in particular, no many grape sequences are available, either as full cDNAs or ESTs. However, it has been proved that analysis of SNPs in expressed genes can be alternatively approached by PCR amplification, using degenerated primers deduced on sequence comparison of highly conserved regions of genes involved in essential metabolic cycles. We concentrated our work on three pathways: sugar and anthocyans metabolism and defence response. To analyse genetic factors potentially affecting sugar quality and sugar yield, anthocyans accumulation and endogenous defence, we designed primers to 20 homologous cDNA and 43 to conserved regions of heterologous cDNAs/ESTs encoding gene products with a role in pathways cited above. Candidate genes to be considered are those encoding functions which represent bottle-necks in the determination of complex traits like the accumulation of carbohydrate , anthocyans and defence related proteins. Such genes, when integrated into a functional map of the genome, can be tested for their association with quantitative trait loci (QTLs). The aim of our work is a step towards the development of a functional map of winegrape. Recently DFLP, CAPS, HD and SSCP analysis which allow the detection of SNPs have been applied to plant genome. The present work will describe the first approach to the SNPs analysis of grape genes related to carbohydrate, nitrogen, anthocyans metabolism and defence response and their association to specific grape linkage groups.