Association of a novel single nucleotide polymorphism at the exon‑2 of Insulin-Like Growth Factor 1 (IGF1) gene with phenotypic variants in goats

the Insulin-Like Growth Factor 1 plays a key role in foetal development and post natal growth.the objectives of this study were to characterise the complete coding sequence of caprine IGF1 gene in two indigenous goat breeds of India: Malabari and attappady Black, to detect polymorphisms of IGF1 gene, to investigate their effects on body size traits and to ascertain the relative expression of IGF1 mrNa in muscle tissues of goats belonging to low and high body weight groups.All the four exons of caprine IGF1 gene were amplified and characterized by PCr-SSCP in 298 goats, revealing two genotypes (CC and Ct) at exon 2. Sequencing of the PCr products from each genotype revealed a novel SNP, g.80C>t (GenBank accession No. kM974180), which caused a non-synonymous mutation (thr48Met),causing differences in IGF1 protein structure.association analysis of the loci indicated Ct genotypes have higher body length (P<0.01),chest circumference (P<0.01) and body length index (P<0.05)than CC genotypes.two novel PCr-rFLPs were designed for the rapid detection of the genotypes.the quantitative real time PCr demonstrated a difference in the expression of IGF1 mrNa in muscle tissues of the low and high body weight groups, but it was not significant (P>0.05).The results of the