Vitis vinifera L. Single-Nucleotide Polymorphism Detection with High-Resolution Melting Analysis Based on the UDP-Glucose:Flavonoid 3-O-Glucosyltransferase Gene.

Vitis vinifera L. is a species with a large number of varieties, which differ in terms of anthocyanin content. The genes involved in the anthocyanin biosynthesis pathway have a direct effect in the anthocyanin profile of each variety, being potentially interesting for varietal identification. The current study aimed at the design of an assay suitable for the discrimination of the largest number of grapevine varieties. Two genes of the anthocyanin pathway, chalcone isomerase (CHI) and UDP-glucose:flavonoid 3-O-glucosyltransferase (UFGT), were sequenced in 22 grapevine varieties. The CHI gene presented 5 SNPs within the sequence. A total of 58 SNPs and 1 INDEL were found among the UFGT gene, allowing the discrimination of 18 different genotypes within the 22 grapevine varieties. A HRM assay designed for UFGT, containing 704 bp, produced differentiated melting curves for each of the 18 haplotypes. The developed HRM assay is efficient in grapevine varietal discrimination.