In an article published online June 8, 2014, in the journal Nature Genetics, a team of researchers affiliated to four different well-known Organizations reported that they have sequenced and assembled a 473-million base pair genome of the common bean, Phaseolus vulgaris. Their study also revealed that the common bean was domesticated separately at two different geographic locations in Mesoamerica and the Andes, diverging from a common ancestral wild population more than 100,000 years ago. The team also compared sequences from pooled populations representing these regions, finding only a small fraction of shared genes. This indicated that different events had been involved in the domestication process at each location.
They found dense clusters of genes related to disease resistance within the chromosomes. They also identified a handful of genes involved in moving nitrogen around. The current practice of inter-cropping ensures that the land can continue to produce high-yield crops without resorting to adding fertilizers or other artificial methods of providing nutrients to the soil.
The team also compared the high quality common bean genome against the sequence of its most economically important relative, soybean. They found evidence of synteny, in which a gene in one species is present in another. They also noted that the common bean’s genome had evolved more rapidly than soybean’s since they diverged from the last common ancestor nearly 20 million years ago.