Uncovered: The First Genetic Analysis of Sweet Potatoes Reveals They Originated as Hybrid Species with a Perplexing History and Six Sets of Chromosomes
In a groundbreaking discovery, a team of researchers led by Professor Anna Müller at the University of Dar es Salaam have successfully decoded the genome of the Tanzania sweet potato. This significant milestone was announced in September 2025 and published in the prestigious journal Nature Plants.
The Tanzania sweet potato, renowned for its abundance and disease resistance, is a segmental allopolyploid, a hybrid from multiple species genetically acting as one. Its complex genetic makeup has long posed a challenge to scientists, making decoding its genome more difficult than other staple crops.
The sweet potato, with its six sets of chromosomes, offers a unique advantage. This polyploid buffering allows the sweet potato to maintain backup copies of important genes, helping it survive drought, resist pests, and adapt to different environments. This resilience is one of the reasons why the sweet potato is a globally important crop.
The decoded genome will enable researchers to improve the sweet potato further, pinpointing genes responsible for high yield, nutritional content, resistance to disease, and more. The techniques pioneered in this study may be used to understand other staple crops such as wheat, cotton, and bananas, which are likely hiding a lot of untapped potential due to their multiple sets of chromosomes.
However, more than one variety of sweet potato will need to be analysed before significant improvements can be made. Some of the ancestors of the sweet potato have not been identified yet, adding another layer of complexity to the research.
The Tanzania variety of sweet potato was the focus of this research due to its prized characteristics. Its resilience is attributed to the multiple sets of chromosomes in the sweet potato, contributing to its enhanced resilience due to polyploid buffering.
This breakthrough in genomic research could pave the way for a new era of crop improvement, ensuring food security and nutritional well-being for millions around the world. Each hectare of farmland dedicated to growing sweet potatoes provides approximately 70 kilocalories per day, making it an efficient staple food.
The decoded genome of the sweet potato opens up a world of possibilities for future research and development, promising a more sustainable and resilient food system for all.
