Relationship between Avian AHR1 Genotype and Ecological Factors as a Dioxin-sensitive Facto

Abstract

　AHR is a transcription factor that is activated by the ligand. Two amino acid residues (Ile_Ser as high sensitivity, Ile_Ala as moderate sensitivity, and Val_Ala as low sensitivity) corresponding to the 324th and 380th positions in the ligand binding domain (LBD) of the chicken AHR1, could be an important factor determining susceptibility to dioxin in avian species. This study showed that ecological factors have driven natural selection pressures on the avian AHR genotypes in the evolutionary process. The association between ecological factors and avian AHR1 LBD genotypes was statistically analyzed. This paper reviews that combinations of certain ecological factors and differential sensitivity to DLCs in avian species could have enforced natural selection pressure on AHR1 genotypes in birds.