Chickens have a wider range of plumage colors than many livestock species. The reason is a single gene capable of producing this entire spectrum.
The research provides an example of how genetic diversity and visible traits can emerge in a short evolutionary period.
In the new one, published this Wednesday in Proceedings of the National Academy of Sciencesresearchers focused on the melanocortin-1 receptor (MC1R), a protein molecule that controls color formation in vertebrate skin cells. The genomes of more than 10 thousand chickens.
According to , the gene that encodes this pigmentation receptor has undergone a high degree of alteration in domestic chickens since its domestication. The team identified 18 variants of this gene, a level of diversity not found in wild birds.
“We demonstrated that the accumulation and recombination of mutations within a single gene gave rise to numerous new variantswith visible effects on the appearance of the birds”, explained the study co-author Claudia Stäubert.
The MC1R works as a molecular switch. Depending on its level of activity, a cell produces more dark pigment or more light pigment.
Through cell cultures, researchers have demonstrated that genetic mutations can increase or decrease the activity of this switch. When several mutations occur at the same time, they can reinforce or neutralize each other, creating color patterns that none of the individual changes could produce on their own.
This study demonstrates how new genetic variants can emerge and spreada principle of evolution that is evident here, over a short evolutionary period of just a few thousand years.
The findings could help animal breeders better predict and selectively influence color traits. In future studies, the researchers plan to investigate whether evolutionary patterns similar to those observed in domestic chickens also occur in other vertebrates.
