An article published in the journal “Nature Communications” reports the results of a new DNA sequencing of Arabica coffee (Coffea arabica, photo of its fruit Forest & Kim Starr) which allowed the identification of various aberrations and genetic diversity. A team of researchers from the University of Udine and the Institute of Applied Genomics (istituto di Genomica applicata, Iga) also in Udine, Italy, used the most advanced genetic techniques to obtain details superior to those of the analyzes conducted in previous years. There’s a commercial purpose because this genetic study was conducted in collaboration with two big Italian producers – Illycaffè and Lavazza – but it’s important to know in depth the DNA of Arabica coffee and also to face the dangers deriving from diseases and climate change.
Almost exactly seven years ago, the first public DNA sequencing of Arabica coffee, the dominant species in the production of the drink, was announced. This species is a hybrid between the species Coffea canephora, commonly known as Robusta, and Coffea eugenioides, so its DNA is made up of four sets of chromosomes. That increased the complexity of genetic analysis and its results obtained in recent years. Sequencing that remained confidential may have been conducted by companies in the sector.
Michele Morgante, from the University of Udine’s Department of Agricultural, Food, Environmental and Animal Sciences and Gabriele Di Gaspero from Iga coordinated this new study. The sequencing was conducted on 174 samples belonging to different species of the Coffea genus, consisting mainly of strains of the Arabica and Robusta species but also one of the other progenitor species Coffea eugenioides.
The results of the sequencing showed that genetic diversity is generally very low in Arabica coffee and is mainly concentrated in strains, in agronomic jargon called cultivars, of the so-called Timor Hybrid. It’s a hybrid born spontaneously in East Timor from a new crossbreeding of Arabica with the Robusta progenitor species.
The researchers also found some genetic aberrations that appear to contribute to the diversity within the Coffea arabica species but also to its resistance to diseases. These are interesting characteristics, also considering that genetic aberrations are generally negative for a species, given that they are mutations that normally cause genetic diseases or that in any case leave the species vulnerable to diseases.
In-depth knowledge of the genetic characteristics of Arabica coffee is important for the producers of the drink to obtain different flavors but also to protect its future. Its resistance to diseases is a decidedly positive trait but also to try to adapt it to climate change.
Other researchers have already examined the possible consequences of drought and other climate-related problems, for example in an article published in the journal “Nature Plants” in December 2022 in which a switch to Liberian coffee (Coffea liberica) was proposed. Commercial and scientific issues are mixed in studies that must also take into account consumer tastes.