Identification of Candidate Genes for Reactivity in Guzerat (Bos indicus) Cattle: A Genome-Wide Association Study

Abstract

Temperament is fundamental to animal production due to its direct influence on the animal-herdsman relationship. When compared to calm animals, the aggressive, anxious or fearful ones exhibit less weight gain, lower reproductive efficiency, decreased milk production and higher herd maintenance costs, all of which contribute to reduced profits. However, temperament is a trait that is complex and difficult to assess. Recently, a new quantitative system, REATEST®, for assessing reactivity, a phenotype of temperament, was developed. Herein, we describe the results of a Genome-wide association study for reactivity, assessed using REATEST® with a sample of 754 females from five dual-purpose (milk and meat production) Guzerat (Bos indicus) herds. Genotyping was performed using a 50k SNP chip and a two-step mixed model approach (Grammar-Gamma) with a one-by-one marker regression was used to identify QTLs. QTLs for reactivity were identified on chromosomes BTA1, BTA5, BTA14, and BTA25. Five intronic and two intergenic markers were significantly associated with reactivity. POU1F1, DRD3, VWA3A, ZBTB20, EPHA6, SNRPF and NTN4 were identified as candidate genes. Previous QTL reports for temperament traits, covering areas surrounding the SNPs/genes identified here, further corroborate these associations. The seven genes identified in the present study explain 20.5% of reactivity variance and give a better understanding of temperament biology.

Genome-wide detection of signatures of selection in indicine and Brazilian locally adapted taurine cattle breeds using whole-genome re-sequencing data

“…We also explored common signals between ROH hotspots and the top 1% putative sweep regions retrieved from both DCMS statistics to increase the power of signals. Among the genes identified when considering the within-population DCMS statistic, we revealed the presence of two interesting genes that have been described to have effects on temperament (EPHA6) [80] and body size (ADAMTS17) [81] in cattle. Further, one gene associated with temperament (ANTXR1) [82] was also highlighted when considering the cross-population DCMS statistic.…”

Genome-wide detection of copy-number variations in local cattle breeds

“…The POU1F1 gene encodes a protein reportedly involved in productive life (Huang et al 2008), whereas PTK2 , FOXF2 (Capomaccio et al 2015) and LAMB3 (Gutiérrez-Gil et al 2015) reportedly encode proteins associated with milk production traits. ZBTB20 is a gene that overlaps the bovine QTL regions associated with milk traits and encodes a transcription factor that has been implicated in hematopoiesis, oncogenesis and the immune response in mammals (dos Santos et al 2017). The SEC24D gene encodes a protein associated with various pathways, including in the immune system and transport to the Golgi, and is involved in transcriptional regulation in cattle (Salleh et al 2017).…”

Influence of genetic markers on the feeding behavior of yearling bulls

“…Recently, Dos Santos et al (2017) identified candidate genes for reactivity in Guzerat (Bos indicus) cattle. One of those genes was ZBTB20, a transcription factor with the potential for association with performance traits such as anxiety, and a strong candidate for reactivity in cattle.…”