Forget about your Trinitario. Let’s get back to the Criollo, the original and best form of the Theobroma cacao. The Maya domesticated the Criollo variety about 3,000 years ago in Central America, and it is one of the oldest domesticated tree crops. But while it still produces the finest possible chocolate, today, many growers prefer to grow hybrid cacao trees (like the Trinitario) that produce chocolate of lower quality but are more resistant to disease.

But enter teams of researchers led by Claire Lanaud of CIRAD, France, with Mark Guiltinan of Penn State, and including scientists from 18 other institutions. They sequenced the DNA of Criolo and expect their research will lead to expanded production of it.

“Our analysis of the Criollo genome has uncovered the genetic basis of pathways leading to the most important quality traits of chocolate — oil, flavonoid and terpene biosynthesis,” said Siela Maximova, associate professor of horticulture, Penn State, and a member of the research team. “It has also led to the discovery of hundreds of genes potentially involved in pathogen resistance, all of which can be used to accelerate the development of elite varieties of cacao in the future.”

The research results have just been published in the journal Nature Genetics.