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Reverse Genetic Approach to Identify Regulators of Pigmentation using Zebrafish
Published on: March 1, 2022
Genomic and transcriptomic insights into color pigmentation variation in barred chickens
Tairan Chen1, Xufang Ren1, Dengjing Zuo1
1National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Yuanmingyuan West Road 2#, Beijing 100193, PR China.
Poultry Science
|June 23, 2026
Summary
Researchers investigated the genetic and molecular basis of yellow-barred versus white-barred feather pigmentation in chickens. They identified candidate genes and gene expression patterns linked to pigment variation, offering insights for poultry breeding.
Area of Science:
- Poultry Genetics
- Animal Genomics
- Molecular Biology
Background:
- Plumage color is economically significant in chickens, with barred patterns showing yellow-barred or white-barred variations.
- The genetic underpinnings of barred patterning are partially understood, but the mechanisms behind pigmentation differences remain unclear.
Purpose of the Study:
- To elucidate the genomic and transcriptomic basis of pigmentation variation in barred chickens.
- To identify candidate genes and molecular pathways contributing to yellow-barred vs. white-barred feather differences.
Main Methods:
- Genome-wide association study (GWAS) and selection signature (FST) analyses were performed on 47 barred chickens.
- Transcriptomic analysis of feather follicles was conducted to identify differentially expressed genes.
- Functional enrichment analysis was used to determine the biological roles of candidate genes.
Main Results:
- GWAS and FST analyses identified candidate genes (e.g., BRINP2, SLC22A4, SLC22A5, ACTN1) associated with pigment variation.
- Transcriptomic analysis revealed 739 differentially expressed genes, including notable candidates like SLC45A2, BCO2, EDAR, KRT75, and KRT14.
- Enrichment analysis highlighted gene involvement in skin development, epidermal differentiation, keratinization, and intermediate filament organization.
Conclusions:
- Coordinated regulation of melanin synthesis, carotenoid metabolism, and feather follicle development underlies observed pigmentation differences.
- This study provides crucial genomic and transcriptomic insights into the molecular basis of feather pigmentation variation in chickens.
- Findings lay the groundwork for future functional validation and molecular breeding strategies in poultry.
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