Association of an insulin‐like growth factor 1 gene microsatellite with phenotypic variation and estimated breeding values of growth traits in Canchim cattle

Abstract

A population of 1398 Canchim (CA) cattle was genotyped to assess the association of an insulin-like growth factor 1 (IGF1) gene microsatellite with phenotypic variation and estimated breeding values of pre-weaning, weaning and post-weaning growth traits. After an initial analysis, the IGF1 genotype only had a significant effect (P < 0.05) on birth weight (BW) and weaning weight adjusted to 240 days (WW240). For these two traits, direct and maternal breeding values were estimated using the restricted maximum likelihood (reml). Two analyses were carried out. In the first (Model I), all fixed effects were fitted. In the second (Model II), the fixed effect of the IGF1 genotype was omitted. The estimated genetic and phenotypic components of variance were similar for every trait in both models. For Model I, estimated direct and maternal heritabilities were 0.26 and 0.16 for BW and 0.23 and 0.14 for WW240 respectively. The genetic and phenotypic correlations between BW and WW240 were 0.38 and 0.38 (Model I) and 0.19 and 0.38 (Model II) respectively. Fifty animals were classified according to their direct and maternal breeding values for both traits. Spearman rank-order correlation between animal rankings in the two models was used to assess the effect of including the IGF1 genotype in the model. Non-significant values from this correlation were indicative of a difference in breeding value rankings between the two approaches. The IGF1 gene was found to be associated with phenotypic variation and breeding values in the early phase of growth.

Candidate genes for production traits in Nelore beef cattle

“…According to Islam et al (2009), several studies have identified a quantitative trait locus (QTL) associated with carcass traits in the vicinity of IGF1 in beef cattle. Several studies have associated polymorphisms in IGF1 with growth traits in beef cattle as well (Pereira et al, 2005;Andrade et al, 2008). Islam et al (2009) have associated an SNP in the promoter region of IGF1, the same region in which the microsatellite used in this study resides with fat deposition and other carcass traits in crossbred Angus and Charolais beef cattle.…”

Polymorphism in the 5ꞌ-UTR of the insulin-like growth factor I gene associated with production traits in Chinese cattle

“…In goats, the microsatellite had effects on birth weight . In cattle, this microsatellite was associated with birth weight and weaning weight in the early growth phase (Andrade et al, 2008).…”

Association of CRTC2 gene polymorphisms with growth and meat quality traits of Qinchuan cattle

“…Growth and meat quality traits are economically important factors of beef cattle and are controlled by multiple genes (Andrade et al, 2008;Liu et al, 2012). Association studies cannot determine whether gene markers are responsible for variations in a trait, or whether such variation is influenced by closely linked loci.…”