Single Nucleotide Polymorphisms in the Chicken Mx gene at Position 2032 by Real-time Allele-specific PCR Melting-curve Analysis

Mx proteins are interferon-induced proteins with potent antiviral activities. A single nucleotide substitution at position 2032 of the Mx gene for position 631 of its protein from Ser to Asn is crucial for its antiviral activities in chickens. This study developed a real-time PCR based allelic discrimination method for the rapid genotyping of the chicken Mx gene G2032A SNP. The previously described allele-specific PCR was combined with real-time PCR melting curving analysis to genotype this Mx gene SNP from a small population of White Leghorn chickens, and the genotyping assay was confirmed by direct sequencing of PCR products. Our data demonstrate that the SNP at position 2032 of the Mx gene can be identified by the characteristic melting curve of the allele-specific fragments. This real-time PCR based SNP assay is rapid, sensitive and easy to perform compared with traditional PCR method which makes it suitable for large population analysis.