Genome Sequencing Reveals What Puts the 'Heat' in Hot Peppers

The genome of the hot pepper, the world's most widely grown spice crop, has been sequenced by a large international team of researchers, including scientists at the University of California, Davis and Seoul National University, Korea.

The researchers sequenced a domesticated variety of hot pepper from the Mexican state of Morelos known as Criolo de Morelos 334. The variety has consistently exhibited high levels of disease resistance and has been extensively used in hot-pepper research and breeding. The sequencing project revealed that blocks of genes appear in much the same chromosomal position in the hot pepper as in tomato, its closest relative. The pepper genome, however, was found to be 3.5-fold larger than the tomato genome.

Sequencing also uncovered evidence suggesting that the pungency, or "heat," of the hot pepper originated through the evolution of new genes by duplication of existing genes and changes in gene expression after the peppers evolved into species.

Highlights of this sequencing effort are in the January 19 Advanced Online publication of Nature Genetics. For more information, read the news release at: http://www.news.ucdavis.edu/search/news_detail.lasso?id=10789.