Analysis reveals 'ultrarapid' gene evolution behind diversity of feather color in chickens – Texas A&M Stories

Researchers at Texas A&M have identified an unexpected genetic process responsible for the wide array of colors and patterns in domestic chickens. By examining over 10,000 chicken genomes, the study confirms that a primary pigmentation gene, known as MC1R, evolves far more rapidly than previously assumed.

Traditionally, scientists believed that individual, isolated mutations were responsible for specific physical traits. However, this study reveals that evolution functions differently in this context. Through a process of genetic recombination, multiple mutations within the MC1R gene reshuffle to create new combinations. Instead of a simple one-to-one relationship between a mutation and a trait, the researchers found that these combinations produce significantly more diversity than the sum of their parts.

Dr. Leif Andersson, a lead professor on the project, notes that the accumulation of these mutations over a relatively short period of time allows for this rapid diversification. This research moves away from the common view that evolutionary change is strictly a slow, linear process. By tracking these patterns, the team demonstrates how organisms can produce new variations through the constant reshuffling of existing genetic material.

This discovery offers practical applications for poultry breeders who focus on maintaining specific breed standards based on color and pattern. Beyond the farm, the findings provide a potential model for understanding how biodiversity arises across the animal kingdom. The team now looks to investigate whether this reshuffling mechanism appears in other species or across different parts of the genome.

This analysis of 10,000 genomes provides a complete picture of the genetic landscape at the MC1R locus. It marks a significant shift in how we understand the speed and mechanics of genetic expression in domestic animals.