Chinese scientists have discovered a second major high-protein gene in corn, a breakthrough that could significantly boost the nutritional value of the crop and reduce China's heavy reliance on imported animal feed.

By combining this newly mapped gene with another discovered by the same team, researchers can increase the protein content of standard corn from 10 percent to 15 percent. For China's most widely planted commercial hybrid corn varieties, grain protein could jump from 8.5 percent to between 12 percent and 13 percent — all without reducing the overall yield.

The findings, representing 15 years of work by a collaborative team from the Center for Excellence in Molecular Plant Sciences at the Chinese Academy of Sciences, Shanghai Normal University, and Sichuan Agricultural University, were published on Wednesday in the journal Nature.

The research carries massive economic implications for China's livestock industry. Protein feed is one of the most expensive and scarce ingredients in diets for pigs, poultry and cattle. Currently, China relies on foreign imports for up to 80 percent of its protein feed materials, primarily soybean meal. In 2025, the country's soybean imports exceeded 100 million metric tons.

Experts estimate that if the protein content of feed corn can be raised by 4 percentage points nationwide, it could slash soybean imports by roughly 30 million tons annually, dramatically shifting the supply-and-demand balance.

While wild ancestors of modern corn boast protein levels as high as 30 percent, those nutritional traits were inadvertently lost over centuries of farming. Because early farmers and modern breeders focused entirely on increasing crop volume and starch, the specific genes responsible for high protein were gradually lost.

In 2022, the research team isolated the first of these lost genes, named THP9-T, from wild corn. Their latest breakthrough centers on a second gene, THP3-T.

"THP3-T acts like the core engine on the nitrogen metabolism production line, encoding an enzyme responsible for efficiently synthesizing amino acids," said Wu Yongrui, a lead scientist on the study.

Wu explained that the team found unique variations in this gene that essentially act as an upgrade to the engine, giving it a stronger "throttle". This allows the corn plant to capture and use nitrogen — a foundational building block for nutrients — much more efficiently to manufacture protein.

When THP3-T works in tandem with the gene discovered in 2022, they form a powerful metabolic center. This genetic teamwork allows the corn to thrive and maintain high protein levels even in low-nitrogen soil, reducing the need for heavy chemical fertilizers.

In livestock production, this high-protein corn could replace between 50 percent to 100 percent of the soybean meal traditionally used in pig feed, and significantly reduce soybean reliance in poultry farming. For farmers and industrial producers, the scientists say the crop will lower overall feed costs, protect national food security, and boost farming incomes.

zhouwenting@chinadaily.com.cn