Selection of Mx gene genotype as genetic marker for Avian Influenza resistance in Indonesian native chicken

BACKGROUND In previous studies, the Mx Gene has been demonstrated to confer positive anti viral responses in chicken. The amino acid variation of Asn (allele A) at position 631 was specific to positive antiviral Mx/resistant, while, that of Ser (allele G) was specific to negative Mx/susceptible. This research was aimed at selecting one of the native chicken breeds which was found out to be resistant to avian influenza using molecular technique. The selected breed will then be used as the base population to improve native chicken breed in Indonesia. METHODS Marker Assisted Selection (MAS) method was used in this research to accelerate the selection process, since the disease resistance had low heritability value. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) technique used to select the genotype of Mx++, Mx+- and Mx-- that corresponded to the positive antiviral activity (Mx++), or those which had positive or negative activity (Mx+-) and negative antiviral activity (Mx--). There were 200 native hens and 40 cocks used in this experiment. Allele frequency of Mx Gene was calculated. The productivity indicators such as age at first laying, egg weight and hen weight at first laying and egg production were also measured. The chicken that had Mx++ and Mx+- genotypes, were selected to produce offspring. RESULTS Result showed that the frequency of the resistant allele (Mx+) was 65% and 60% in laying hens and in cocks, respectively, while the frequency of the susceptible allele (Mx-) was 35% and 40% in hens and cocks, resepctively. Age, egg weight and hen weight at first laying and egg production for susceptible genotype were slightly better than for the resistant genotype which were 172,41 VS 178,81 days; 33,94 VS 32,84 g; 1450 VS 1439 g and 54,32 VS 48,30 %, respectively.