Genome-Wide Detection of CNVs and Their Association with Meat Tenderness in Nelore Cattle

PLoS One. 2016 Jun 27;11(6):e0157711. doi: 10.1371/journal.pone.0157711. eCollection 2016.

Abstract

Brazil is one of the largest beef producers and exporters in the world with the Nelore breed representing the vast majority of Brazilian cattle (Bos taurus indicus). Despite the great adaptability of the Nelore breed to tropical climate, meat tenderness (MT) remains to be improved. Several factors including genetic composition can influence MT. In this article, we report a genome-wide analysis of copy number variation (CNV) inferred from Illumina® High Density SNP-chip data for a Nelore population of 723 males. We detected >2,600 CNV regions (CNVRs) representing ≈6.5% of the genome. Comparing our results with previous studies revealed an overlap in ≈1400 CNVRs (>50%). A total of 1,155 CNVRs (43.6%) overlapped 2,750 genes. They were enriched for processes involving guanosine triphosphate (GTP), previously reported to influence skeletal muscle physiology and morphology. Nelore CNVRs also overlapped QTLs for MT reported in other breeds (8.9%, 236 CNVRs) and from a previous study with this population (4.1%, 109 CNVRs). Two CNVRs were also proximal to glutathione metabolism genes that were previously associated with MT. Genome-wide association study of CN state with estimated breeding values derived from meat shear force identified 6 regions, including a region on BTA3 that contains genes of the cAMP and cGMP pathway. Ten CNVRs that overlapped regions associated with MT were successfully validated by qPCR. Our results represent the first comprehensive CNV study in Bos taurus indicus cattle and identify regions in which copy number changes are potentially of importance for the MT phenotype.

MeSH terms

  • Animals
  • Cattle / genetics*
  • DNA Copy Number Variations*
  • Genome-Wide Association Study
  • Meat / standards*
  • Muscle, Skeletal / metabolism
  • Quantitative Trait Loci*

Grants and funding

VHS received a scholarship from São Paulo Research Foundation (FAPESP, grant numbers: 2012/23717-5 <http://www.bv.fapesp.br/en/bolsas/141514/identification-of-cnvs-in-the-nelore-genome-and-its-association-with-meat-tenderness/> and 2014/01438-2 <http://www.bv.fapesp.br/en/bolsas/150170/metabolic-pathways-and-meat-tenderness-from-cnvs-to-gene-expression-in-nelore-cattle-breed/>). LAR and LC were granted by National Counsel of Technological and Scientific Development (CNPq) fellowships. The thematic FAPESP grant number is 2012/23638-8.