Polymorphism of Insulin-like Growth Factor 1 Gene (IGF1/TasI, IGF1/SnaBI, IGF1/RsaI) and the Association with Daily Gain of Pesisir Cattle Local Breed from West Sumatera, Indonesia.

BACKGROUND AND OBJECTIVE: The insulin-like growth factor 1 gene (IGF1) is a candidate gene for marker-assisted selection strategies. Two single nucleotide polymorphism of IGF1 gene namely IGF1/SnaBI and IGF1/TasI has been reported to be associated with production traits in several cattle breeds. One single nucleotide polymorphism in exon 4 namely IGF1/Rsa1 has a significant influence (p<0.01) on birth weight, weaning weight and average daily gain of Bali cattle. The objective of this study was to determine the IGF1/SnaBI, IGF1/TasI and IGF1/RsaI polymorphisms and their associations with average daily gain in Pesisir cattle local breed from west Sumatera Indonesia.

METHODOLOGY: The isolation of DNA from 183 blood sample was performed using DNA extraction kit (Promega DNA purification kit) following the manufacture procedure. The amplification of IGF1 fragment was done by master mix from Thermo Scientific.

RESULTS: In the case of the IGF1/SnaBI polymorphism, three genotypes were observed, frequencies were 0.011, 0.011 and 0.978 for AA, AB and BB, respectively. This gives frequencies of 0.064 and 0.9836 for A and B alleles. For IGF1-TasI locus showed that AA genotype occurred with a frequency of 0.978, AC with 0.011 and CC with 0.011 with frequency for allele A and C were 0.9836 and 0.0164, respectively. In the case IGF1/RsaI polymorphism produces only TT and CT genotype with frequency 0.027 and 0.973 respectively and frequency of T and C allele were 0.5137 and 0.4863, respectively.

CONCLUSION: Among these 3 polymorphism only IGF1/RsaI was associated with average daily gain, Thus this polymorphism could be a potential for improving body weight in Pesisir cattle. Association study for IGF1/SnaBI and IGF1/TasI were strongly limited by low frequency of one allele.