Related Experiment Video
Updated: Aug 12, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Genome-Wide Association Study Reveals Candidate Genes Associated With the Intensity of Green Eggshell Color in
Yongguang Zhou1,2, Shenjun Wu1,2, Jiaxuan Zhang1
1College of Animal Science and Technology, China Agricultural University, Beijing, China.
Animal Genetics
|August 10, 2026
Summary
Researchers identified the genetic basis for green eggshell color intensity in chickens. A genome-wide association study pinpointed the ALAS1 gene, offering markers for breeding programs to enhance this economic poultry trait.
Area of Science:
- Poultry Genetics
- Animal Breeding
- Biochemistry
Background:
- Eggshell color is an important economic trait in poultry.
- Green eggshell color intensity in chickens is linked to biliverdin deposition, but its genetic underpinnings are not fully understood.
Purpose of the Study:
- To identify the genetic factors influencing green eggshell color intensity in Dongxiang green-eggshell chickens.
- To find candidate genes and genetic markers for improving green eggshell color in poultry breeding.
Main Methods:
- Genome-wide association study (GWAS) was performed on 230 Dongxiang green-eggshell chickens.
- Eggshell biliverdin concentration was used as the phenotype.
- Significant single nucleotide polymorphisms (SNPs) and candidate genes were identified through genotyping and functional annotation.
Main Results:
- All 230 chickens were homozygous for the green-shell genotype.
- GWAS identified seven significant SNPs within a 110-kb region on chromosome 12.
- The ALAS1 gene, encoding a key enzyme in heme biosynthesis, was identified as a strong candidate gene.
Conclusions:
- The ALAS1 gene region is strongly linked to green eggshell color intensity.
- Candidate genetic markers associated with ALAS1 can be utilized in poultry breeding programs to enhance green eggshell color intensity.
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