Assessing MHC-B diversity in Silkie chickens

Poult Sci. 2020 May;99(5):2337-2341. doi: 10.1016/j.psj.2020.01.005. Epub 2020 Mar 19.

Abstract

The major histocompatibility complex (MHC) is a highly polymorphic region on chromosome 16, which contains numerous immune response genes, and is known to influence disease susceptibility and resistance in chickens. Variability of MHC-B haplotypes in various well-known and commercially utilized breeds has previously been identified. This study aims to understand MHC-B diversity in the Silkie breed using a high-density SNP panel that encompasses the chicken MHC-B region. DNA was obtained from 74 females and 27 males from a commercial Silkie breeder colony that is maintained through minimal genetic selection practices. A previously described panel of 90 SNPs, all located within the MHC-B region, was used to evaluate MHC-B variability in the commercial Silkie breeder colony. MHC-B haplotypes identified from the individual SNP information in the Silkie colony were compared to published haplotypes from the same region. Of the 27 haplotypes identified in the Silkie population, 8 have been previously described. Nineteen haplotypes are unique to the Silkie population and include one novel recombinant and 2 additional possible novel recombinants. Six haplotypes were found at a frequency greater than 5% of the population, of which 4 are novel. Finally, Hardy Weinberg Equilibrium (HWE) was calculated for the observed haplotypes, which were found to be in HWE. This study shows considerable MHC-B diversity in the Silkie breed and adds further information on variability of the MHC-B region in the chicken.

Keywords: MHC-B; SNP; Silkie; haplotype.

MeSH terms

  • Animals
  • Avian Proteins / genetics*
  • Breeding
  • Chickens / genetics*
  • Disease Resistance / genetics
  • Female
  • Genetic Variation*
  • Genome
  • Haplotypes
  • Major Histocompatibility Complex / genetics*
  • Male
  • Poultry Diseases / genetics

Substances

  • Avian Proteins