In recent days at the 25th Plant and Animal Genome Conference held in San Diego the details of the sequencing of the DNA of arabica coffee – species Coffea arabica – were presented. Among the species of coffee it’s the dominant one making up about 70% of the drink’s production. A team of researchers at the University of California, Davis (UC Davis) made the first public sequencing in order to contribute to improving its quality and develop varieties adapted to climate change.
Arabica coffee is a hybrid derived from two other species of coffee: Coffea canephora, commonly known as robust, and Coffea eugenioides. The consequence is that arabica has a DNA formed by four sets of chromosomes, two for each of the original species. The genome of the robusta coffee was sequenced in 2014 because that species is also cultivated to produce the drink. In the case of arabica, so far there were no sequencing with public results but it’s possible that companies in the sector made it keeping its results reserved.
Suntory, a Japanese company that also operates in the coffee field, funded the sequencing of arabica coffee in a collaboration with UC Davis. In this case, the results haven’t only been announced but the information was already partly made available at the Phytozome website, the genomic site of the US Department of Energy’s Joint Genome Institute.
In particular, the researchers took samples for the genome extraction from a very fine variety arabica coffee called Geisha which origin, despite its name, is in western Ethiopia’s mountains. Both DNA and RNA were taken from 23 Geisha trees and the sequencing revealed that the genome of one of the trees is formed by 1.19 billion bases and an estimate of 70,830 genes, approximately one third of human’s DNA.
This research has certainly some commercial purposes considering that it also aims to improve the quality of arabica coffee with handsome profits for the companies that will succeed in obtaining it. However, another goal is to find new ways to adapt this species to live in climates that are changing and also to resist various diseases.
These are serious problems because in recent years many coffee plantations, as well as those of other plants, are undergoing damage caused by the impact of climate changes. New crops are undergoing testing in California but it would be helpful to understand from the analysis of arabica coffee’s DNA how to cultivate it in conditions different from those in which it normally grows. Given the huge appreciation for coffee, it’s a problem that concerns really a lot of people.