Unraveling the associations of osteoprotegerin gene with production traits in a paternal broiler line

Abstract

Improvements on growth and carcass traits in the poultry industry have been achieved by intense selection for heavier chickens at early ages. This faster growth has caused serious problems due to insufficient skeletal structure development needed to support the musculature of modern broilers. The osteoprotegerin gene (OPG), located on GGA2, is an important regulator of bone metabolism and reabsorption, being suggestive as a possible functional candidate gene associated with bone integrity in chickens. This study reports associations of a single nucleotide polymorphism (SNP) in the OPG gene with production traits in a parental broiler line. Different phenotypic groups were evaluated: performance, carcass and skeletal traits. SNPs were identified within the OPG gene and the most informative SNP g.9144C > G was chosen for association analyses. Chickens (n = 1230) were genotyped using PCR-RFLP. The association was carried out with QxPaK v4.0 software using a mixed model including sex, hatch and SNP as fixed effects, and the infinitesimal and residual as random effects. The OPG SNP was associated with important traits as body weight at 21 days, weights of tibia and drumstick skin, leg muscle yield, and tibia breaking strength (P < 0.05). Associations were explained by the additive effect of the SNP and the additive effect within sex. This SNP could be considered a potential marker to improve bone resistance in chickens; however, caution should be taken because of its negative effect in other important traits evaluated in this study. Furthermore, these findings suggest a possible involvement of the OPG gene in fat deposition in poultry.Electronic supplementary materialThe online version of this article (doi:10.1186/2193-1801-3-682) contains supplementary material, which is available to authorized users.

Association of RUNX2 and TNFSF11 genes with production traits in a paternal broiler line

“…Park et al (2006) identified a QTL region associated with abdominal fat in broilers, where the TNFSF11 gene is mapped. Moreover, Fornari et al (2014) found significant (P < 0.05) associations between the osteoprotegerin gene (TNFRSF11B) and AFW and AFY traits in the same population used in this study. The TNFRSF11B gene acts as a decoy receptor of the TNFSF11 gene (Boyle et al, 2003).…”

“…Further studies are required to elucidate the possible causes of the associations found in this study since the direct effect of the mutations, interactions with other genes, and/or the linkage disequilibrium between the SNPs and causative mutations resulting from an indirect effect (Fornari et al, 2014) may be responsible for the associations of the two SNPs studied here with several traits in this broiler population.…”

“…A total of 79 traits from the TT Reference Population database were evaluated, including traits related to broiler performance, carcass composition, organs, and bone integrity (see Table S1). The descriptive statistics of those traits were described by Fornari et al (2014).…”

“…Da observed significant associations (P < 0.05) of single-nucleotide polymorphism (SNP) g.729C>T of the ADIPOR1 (adiponectin receptor 1) gene with bone integrity traits and breast skin yield in the same population of broilers, suggesting that this gene can act in metabolism, fat deposition, and bone integrity. Fornari et al (2014) found that the SNP g.9144C>G in the TNFRSF11B (osteoprotegerin) gene was associated with skeletal structure, performance, and carcass traits in the TT Reference Population of broilers. Genetic associations were also found between the ACTA1 (actin, alpha1, skeletal muscle) gene and performance and carcass traits in the same population (Venturini et al, 2015).…”

Polymorphisms in GJA1 and their association with growth traits in chicken

“…Genetic polymorphisms in the exon region of the GJA1 gene have been positively associated with various diseases in human (Kogame et al, 2014;Jamsheer et al, 2014), mice (Flenniken et al, 2005), and fish (Iovine et al, 2005). No available data associate the chicken GJA1 gene with growth traits, though several studies have been performed on other genes (Sato et al, 2012;Fornari et al, 2014) in chicken and have shown positive correlations with growth traits. Therefore, our discovery of a synonymous mutation in the chicken GJA1 gene and its significant association with growth traits suggests that this polymorphism could be used as a molecular marker for growth or muscle development traits in chicken.…”