Potato’s Ancient Hybrid Origin Uncovered

Interbreeding Event Gave Rise to Tuberous Staple

The potato, a vital global food source, owes its existence to a remarkable 8- to 9-million-year-old hybridization event between ancient tomato-like species and potato-like relatives from South America.

Evolutionary Breakthrough Triggered Tuber Formation

This ancient cross-breeding sparked the development of the tuber, the nutrient-rich underground storage organ characteristic of potatoes, yams, and taros. A multinational team of biologists made this discovery through comprehensive genomic analysis.

The study, published in the journal Cell, analyzed 450 genomes from cultivated potatoes and 56 wild relatives. Researchers found that all potato species possess a stable genetic blend inherited from both the “Etuberosum” lineage and tomato ancestors.

“Our findings show how a hybridization event between species can spark the evolution of new traits, allowing even more species to emerge.”

—Sanwen Huang, Agricultural Genomics Institute at Shenzhen

“We’ve finally solved the mystery of where potatoes came from,” stated **Sanwen Huang** of the Chinese Academy of Agricultural Sciences. The extensive dataset represents the most thorough collection of wild potato genomic data ever examined, according to researcher **Zhiyang Zhang**.

Key Genes from Both Ancestors Essential for Tubers

The potato’s ability to form tubers is attributed to a combination of genes from its parent species. The critical gene *SP6A*, which initiates tuber formation, was inherited from the tomato side of the family.

Another crucial gene, *IT1*, responsible for regulating the growth of underground stems that develop into tubers, originated from the Etuberosum lineage. Without these genes, the hybrid offspring would not have been able to produce tubers.

This evolutionary innovation coincided with the rapid geological uplift of the Andes Mountains, leading to new environmental conditions. The ability to store nutrients in tubers allowed early potatoes to adapt to these harsh mountainous environments and reproduce efficiently without relying solely on seeds.

The potato is now the world’s third-largest staple crop, crucial for global food security. In 2022, global potato production exceeded 370 million metric tons (FAOSTAT).

This adaptability fueled the rapid expansion of potato species across diverse ecological niches, from temperate grasslands to cold alpine meadows, contributing to the rich diversity seen today.