An international team led by the Agricultural Genomics Institute at Shenzhen has traced the origins of the modern potato to a single hybridisation event between a wild tomato ancestor and the Chilean plant group Etuberosum roughly nine million years ago. The findings, published on Thursday in the journal Cell, overturn decades of debate about the crop’s lineage and confirm that potatoes are not direct descendants of tuber-less Etuberosum alone. Researchers analysed 450 genomes from cultivated potatoes and 56 wild relatives, building more than 3,000 phylogenetic trees. Every specimen carried a stable genetic mix—about 60 percent from Etuberosum and 40 percent from tomatoes—pointing to one ancient crossover rather than multiple later exchanges. Two critical genes illustrate the divide of labour: SP6A, inherited from tomato, acts as the master switch that tells the plant to form tubers, while IT1, from Etuberosum, governs the underground stem that fattens into the edible spud. With global potato production exceeding 350 million tonnes a year, the genetic map offers a new toolkit for breeders confronting climate stress, disease and yield constraints. By re-introducing or editing ancestral tomato and Etuberosum genes, scientists hope to develop seed-propagated varieties that grow faster, survive harsher conditions and reduce reliance on clonal planting—extending the legacy of an evolutionary accident that shaped one of the world’s staple foods.