02878naa a2200277 a 450000100080000000500110000800800410001902400350006010000170009524501270011226000090023950003070024852017280055565300160228365300200229965300250231965300180234465300160236270000170237870000170239570000210241270000190243370000160245270000190246877301130248710574172022-12-13       2018    bl uuuu     u00u1 u    #d7 a10.1017/S17517311170015622DOI1 aMOTTA, R. R.  aAnalyses of reaction norms reveal new chromosome regions associated with tick resistance in cattle.h[electronic resource]  c2018  aArticle history: Received 12 December 2016; Accepted 22 May 2017; Published online: 13 July 2017. Corresponding author: R.R. Mota, Gembloux Agro-Bio Tech Faculty, TERRA Teaching and Research Centre, University of Liège, B-5030 Gembloux, Belgium,  rrmota@ulg.ac.be --  License Under a Creative Commons.  aABSTRACT.- Despite single nucleotide polymorphism (SNP) availability and frequent cost reduction has allowed genome-wide association studies even in complex traits as tick resistance, the use of this information source in SNP by environment interaction context is unknown for many economically important traits in cattle. We aimed at identifying putative genomic regions explaining differences in tick resistance in Hereford and Braford cattle under SNP by environment point of view as well as to identify candidate genes derived from outliers/significant markers. The environment was defined as contemporary group means of tick counts, since they seemed to be the most appropriate entities to describe the environmental gradient in beef cattle. A total of 4363 animals having tick counts (n=10 673) originated from 197 sires and 3966 dams were used. Genotypes were acquired on 3591 of these cattle. From top 1% SNPs (410) having the greatest effects in each environment, 75 were consistently relevant in all environments, which indicated SNP by environment interaction. The outliers/significant SNPs were mapped on chromosomes 1, 2, 5, 6, 7, 9, 11, 13, 14, 15, 16, 18, 21, 23, 24, 26 and 28, and potential candidate genes were detected across environments. The presence of SNP by environment interaction for tick resistance indicates that genetic expression of resistance depends upon tick burden. Markers with major portion of genetic variance explained across environments appeared to be close to genes with different direct or indirect functions related to immune system, inflammatory process and mechanisms of tissue destruction/repair, such as energy metabolism and cell differentiation. © The Animal Consortium 2017  aBEEF CATTLE  aCANDIDATE GENES  aENVIRONMENT GRADIENT  aGENE FUNCTION  aSINGLE-STEP1 aSILVA, F. F.1 aLOPES, P. S.1 aTEMPELMAN, R. J.1 aSOLLERO, B. P.1 aAGUILAR, I.1 aCARDOSO, F. F.  tAnimal, 2018, volume 12, Issue 2, pages 205-214. OPEN ACCESS. doi: https://doi.org/10.1017/S1751731117001562