Grapevines retain a molecular memory through centuries of cloning

For centuries, winemakers have produced Cabernet Sauvignon through vegetative propagation, essentially cloning the vines to ensure consistency. A new study reveals that these plants pass down more than just their genetic sequence; they also inherit a remarkable amount of 'epigenetic' information. Researchers investigated DNA methylation—chemical tags that attach to the genome to regulate gene activity—in Cabernet Sauvignon and its parental lineages, Cabernet Franc and Sauvignon Blanc.

To capture the full picture, the team utilised a 'phased sequence graph'. Unlike traditional linear maps, this advanced framework distinguishes between the chromosome copies inherited from each parent. The results showed that while methylation marks are slightly less conserved than the DNA sequence itself, they remain incredibly stable through asexual reproduction. This finding challenges the limitations of standard linear references, demonstrating that graph-based modelling is crucial for accurate analysis. Ultimately, understanding this hidden layer of inheritance could prove vital for the future breeding and adaptation of perennial crops facing agricultural challenges.