Association of SNPs in dopamine and serotonin pathway genes and their interacting genes with temperament traits in Charolais cows

Abstract

Cattle temperament is a complex trait, and molecular studies aimed at defining this trait are scarce. We used an interaction networks approach to identify new genes (interacting genes) and to estimate their effects and those of 19 dopamine- and serotonin-related genes on the temperament traits of Charolais cattle. The genes proopiomelanocortin (POMC), neuropeptide Y (NPY), solute carrier family 18, member 2 (SLC18A2) and FBJ murine osteosarcoma viral oncogene homologue (FOSFBJ) were identified as new candidates. Their potential to be associated with temperament was estimated according to their reported biological activities, which included interactions with neural activity, receptor function, targeting or synthesis of neurotransmitters and association with behaviour. Pen score (PS) and exit velocity (EV) measures were determined from 412 Charolais cows to calculate their temperament score (TS). Based on the TS, calm (n = 55; TS, 1.09 ± 0.33) and temperamental (n = 58; TS, 2.27 ± 0.639) cows were selected and genotyped using a 248 single-nucleotide variation (SNV) panel. Of the 248 variations in the panel, only 151 were confirmed to be polymorphic (single-nucleotide polymorphisms; SNPs) in the tested population. Single-marker association analyses between genotypes and temperament measures (EV, PS and/or TS) indicated significant associations of six SNPs from four candidate genes. The markers rs109576799 and rs43696138, located in the DRD3 and HTR2A genes, respectively, were significantly associated with both EV and TS traits. Four markers, rs110365063 and rs137756569 from the POMC gene and rs110365063 and rs135155082 located in SLC18A2 and DRD2, respectively, were associated with PS. The variant rs110365063 located in bovine SLC18A2 causes a change in the amino acid sequence from Ala to Thr. Further studies are needed to confirm the association of genetic profile with cattle temperament; however, our study represents important progress in understanding the regulation of cattle temperament by different genes with divergent functions.

Demography and rapid local adaptation shape Creole cattle genome diversity in the tropics

“…In addition, we found regions enriched for genes associated with heat tolerance, including regulation of blood pressure and, importantly, thermoregulation in lactating cows exposed to heat stress in the Florida Cracker (region #24). This region in BTA26 showed a strong increase in zebu ancestry (43%, more than three SD) and was also implicated in temperament, with the SLC18A2 gene involved in the dopamine and serotonin pathways associated with temperament in cows (Garza-Brenner et al, 2017). Phenotypic variation driven by production aims, such as beef or dairy traits, may have had an impact in the genomic areas under selection, highlighted here by the regions detected within QTLs associated with milk and meat production, fatty acid profile, performance, conformation and reproduction.…”

Influence of temperament-related genes on live weight traits of Charolais cows

“…No significant associations were found for YW. Genetic diversity parameters of the ten SNP are shown in Table 5, while in Table 6, the least square means of each growth trait are reported, also including the least square means data of temperament traits (Garza-Brenner et al, 2017). Seven markers (rs41749779 [DRD2]; rs134256715 [MAOA; monoamine serotonin 5-hydroxytryptamine receptor 2A]) were associated with BW, in which the most significant associations were observed for markers rs41749779 and rs134256715 (P = 0.008 and P = 0.002, respectively).…”

“…Pen score was assessed by three evaluators using a five-point scale, with scores ranging from 1 (calm) to 5 (moving aggressively), as described by Hammond et al (1996). Individual temperament score (TS) values were calculated by averaging the PS and EV [TS = (PS + EV)/2] (Garza-Brenner et al, 2017). Records of PS, EV, and TS were obtained for each animal from the available database of the Animal Biotechnology Laboratory; these data were recorded once at the time of hair sampling from each animal (Garza-Brenner et al, 2017).…”

“…From the 412 analyzed cows, a group of 80 individuals identified as the most docile (n = 41) and temperamental (n = 39) were genotyped with a 151 SNP panel using the Sequenom MassARRAY ® platform (GeneSeek, Inc., Lincoln, NE, USA). All SNP were selected from a previously reported SNV (single nucleotide variations) panel described by Garza-Brenner et al (2017). The ID and gene location of each SNP are described in Table 1.…”

“…Previous studies have identified growth-influencing genes in Mexican Charolais cattle (Jahuey-Martínez et al, 2016). Garza-Brenner et al (2017) identified new genes and polymorphisms associated with bovine temperament as well as specific single-nucleotide polymorphisms (SNP) that showed effects on temperament-related traits such as EV and pen score (PS). Previous reports have not determined the effect of these genes on both characteristics (growth traits and temperament); however, these genes could have this potential due to their reported biological activities (e.g., the genes proopiomelanocortin [POMC], neuropeptide Y [NPY], and certain genes belonging to the solute carrier family [SLC18A2]).…”