IGF-1 Gene Polymorphism in Migratory Gaddi Goats of Western Himalayan Region, India

ABSTRACT

Goat production is a predominant livestock activity in harsh climatic regions of the country particularly hilly regions. ‘Gaddi’ is a prominent goat breed of Himachal Pradesh constituting 60-65% of total goat population of 11.20 lakh (19th Livestock Census, 2012). The somatotropic axis has a key role in postnatal growth and metabolism. IGF-1 gene encodes the protein that is structurally and functionally similar to insulin and regulates cellular synthesis of DNA as well as cellular growth and development, especially in neurons and also mediates the effect of GH gene. The present study was carried onÊ»Gaddiʼ, a distinct goat breed of high altitude areas of Western Himalayan region, for molecular characterization of IGF-1 gene and further analyse its association with growth traits. Blood samples from 63 genetically unrelated animals of Gaddi goat breed were taken from the migratory flocks under AICRP and Gaddi goat unit of CSKHPKV, Palampur and subjected to DNA isolation. 363 bp amplicon was generated and PCR-RFLP analysis using HaeIII restriction enzyme (RE) revealed two variants (AB and BB) however, no significant association could be established. Allele frequencies for A and B alleles were 0.25 and 0.75. The estimates obtained for Ne, Hobs, Hexp and PIC were 1.61, 0.51, 0.38 and 0.31, respectively. PIC value of 0.31 implies the effectiveness of the marker in population studies and also revealed median level of polymorphism. Sequencing confirmed one nucleotide mutation (C264G), however, no significant association were found at IGF-1 genotype with biometric traits in screened Gaddi goats