# TaqMan® and HRM approaches for SNP genotyping in genetic traceability of musts and wines

## TL;DR

The study developed and tested SNP markers using TaqMan® and HRM techniques to identify grape varieties in musts and wines, aiming to prevent fraud in the wine industry.

## Contribution

The study introduces and validates new SNP markers for varietal identification in musts and wines using TaqMan® assays.

## Key findings

- TaqMan® assays proved more reliable than HRM for SNP genotyping in musts and wines.
- Barbera, Dolcetto, and Arneis were successfully identified in experimental and commercial wines using TaqMan®.
- Dolcetto-based musts/wines showed more efficient varietal identification than Arneis-based wines.

## Abstract

The fight against fraud in the wine sector requires continuous improvements and validations of new technologies applicable to musts and wines. Starting from published data from the Vitis18kSNP array, a series of new specific single nucleotide polymorphism (SNP) markers have been identified for some important north-western Italian cultivars, such as Barbera, Dolcetto and Arneis (Vitis vinifera L.), used in the production of high-quality wines under Protected Denomination of Origin. A pair of new SNP markers for each grape variety were selected and validated using two real-time PCR techniques: TaqMan® genotyping assays and high-resolution melting analysis (HRM). The TaqMan® assay has proven to be more reliable and repeatable than HRM analysis because despite being an economical and versatile technique for the detection of different types of genomic mutations (SNPs, insertions or deletions), HRM has shown limitations in the presence of poor-quality DNA extracted from musts and wines. TaqMan® assays have successfully identified Barbera, Dolcetto and Arneis in their respective musts and experimental wines, and with good efficiency in commercial wines. Marked differences between genotypes were observed, varietal identification in Dolcetto-based musts/wines was more efficient than that in Arneis-based wines. Therefore, the TaqMan® assay has considerable potential for varietal identification in wines and the procedure described in the present work can be easily adapted to all wines with adequate setup of DNA extraction methods that should be adapted to different wines.

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•Single nucleotide polymorphism (SNP) markers specific for different grape varieties.•SNP markers detected by TaqMan® genotyping assays and HRM analysis.•TaqMan® assays have successfully identified experimental and commercial wines.•SNP genotyping are promising method for varietal identification in wine.

Single nucleotide polymorphism (SNP) markers specific for different grape varieties.

SNP markers detected by TaqMan® genotyping assays and HRM analysis.

TaqMan® assays have successfully identified experimental and commercial wines.

SNP genotyping are promising method for varietal identification in wine.