02850naa a2200229 a 450000100080000000500110000800800410001902200210006002400310008110000190011224501310013126000090026250005450027152016200081665300080243665300200244465300110246470000160247570000130249170000190250477300970252310635482022-08-30       2022    bl uuuu     u00u1 u    #d  ae-ISSN 2073-44257 a10.3390/genes130915482DOI1 aCARRACELAS, B.  aGenome-wide association study of parasite resistance to gastrointestinal nematodes in Corriedale sheep.h[electronic resource]  c2022  aArticle history: Received 25 May 2022; Revised 19 August 2022; Accepted 23 August 2022; Published 27 August 2022. Correspondence: gciappesoni@inia.org.uy -- Academic Editor: Qiuyue Liu.  License: This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). This article belongs to the Collection Feature Papers in Animal Genetics and Genomics: https://www.mdpi.com/journal/genes/topical_collections/feature_paper_animal  aABSTRACT.- Selection of genetically resistant animals is one alternative to reduce the negative impact of gastrointestinal nematodes (GIN) on sheep production. The aim of this study was to identify genomic regions associated with GIN resistance in Corriedale sheep by single-step genome-wide association studies (ssGWAS) using 170, 507 and 50K single nucleotide polymorphisms (SNPs). Analysis included 19,547 lambs with faecal egg counts (FEC) records, a pedigree file of 40,056 animals and 454, 711 and 383 genotypes from 170, 507 and 50K SNPs, respectively. Genomic estimated breeding values (GEBV) were obtained with single-step genomic BLUP methodology (ssGBLUP), using a univariate animal model, which included contemporary group, type of birth and age of dam as class fixed effects and age at FEC recording as covariate. The SNP effects as wells as p-values were estimated with POSTGSF90 program. Significance level was defined by a chromosome-wise False Discovery Rate of 5%. Significant genomic regions were identified in chromosomes 1, 3, 12 and 19 with the 170 SNP set, in chromosomes 7, 12 and 24 using the 507 SNP chip and only in chromosome 7 with the 50K SNP chip. Candidate genes located in these regions, using Oar_v4.0 as reference genome, were TIMP3, TLR5, LEPR and TLR9 (170 SNPs), SYNDIG1L and MGRN1 (507 SNP chip) and INO80, TLN2, TSHR and EIF2AK4 (50K SNP chip). These results validate genomic regions associated with FEC previously identified in Corriedale and other breeds and report new candidate regions for further investigation. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.  aFEC  aGenomic regions  aSsGWAS1 aNAVAJAS, E.1 aVERA, B.1 aCIAPPESONI, G.  tGenes, 2022, vol. 13, issue 9, 1548. OPEN ACCESS. doi: https://doi.org/10.3390/genes13091548