Allelic polymorphism of insulin-like growth factor 1 gene and its relationship with growth traits in repeated backcrossed laying chickens

Abstract

The relationship of insulin-like growth factor-1 (IGF-1) polymorphism with growth traits was investigated in repeated backcrossed laying chickens reared in derived savanna zone of Nigeria which was conducted at Poultry Unit of Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso, Oyo state, Department of Animal Breeding and Genetics, Biotechnology Laboratory , Federal University of Agriculture, Abeokuta, Ogun State. Nigeria. One-hundred and thirty-three birds were used for the study and comprises of 4 different genotypes. Genomic DNA was extracted from obtained bloods and the polymorphism of IGF-I gene was detected by PCR-RFLP-PstI. Both allelic and genotypic frequencies were calculated and Statistical analysis of data was done using LSD (least significant difference) method as applied in the General Linear Model (GLM) procedure (SAS 9.1). Genotyping of birds revealed two alleles A (0.54), C (0.46) and three genotypes AA (41), AC (60), CC (32). AC genotype has the highest frequency of 53% while for AA and CC the frequencies are 30% and 17% among selected repeated backcrossed chickens. Analyzing different genotypes reveals non- significant effects on growth traits of the chickens involved. Based on the results of this study, the application of IGF-1 locus in Marker Assisted Selection programs can be advised.