Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population

Gastrointestinal (GI) parasitic infection is the main health constraint for small ruminant production, causing loss of weight and/or death. Red Maasai sheep have adapted to a tropical environment where extreme parasite exposure is a constant, especially with highly pathogenic Haemonchus contortus. T...

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Autores principales: Benavides, M.V., Sonstegard, T.S., Kemp, Stephen J., Mugambi, J.M.M., Gibson, John P., Baker, R.L., Hanotte, Olivier H., Marshall, Karen, Tassell, C. van
Formato: Journal Article
Lenguaje:Inglés
Publicado: Public Library of Science 2015
Materias:
Acceso en línea:https://hdl.handle.net/10568/72426
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author Benavides, M.V.
Sonstegard, T.S.
Kemp, Stephen J.
Mugambi, J.M.M.
Gibson, John P.
Baker, R.L.
Hanotte, Olivier H.
Marshall, Karen
Tassell, C. van
author_browse Baker, R.L.
Benavides, M.V.
Gibson, John P.
Hanotte, Olivier H.
Kemp, Stephen J.
Marshall, Karen
Mugambi, J.M.M.
Sonstegard, T.S.
Tassell, C. van
author_facet Benavides, M.V.
Sonstegard, T.S.
Kemp, Stephen J.
Mugambi, J.M.M.
Gibson, John P.
Baker, R.L.
Hanotte, Olivier H.
Marshall, Karen
Tassell, C. van
author_sort Benavides, M.V.
collection Repository of Agricultural Research Outputs (CGSpace)
description Gastrointestinal (GI) parasitic infection is the main health constraint for small ruminant production, causing loss of weight and/or death. Red Maasai sheep have adapted to a tropical environment where extreme parasite exposure is a constant, especially with highly pathogenic Haemonchus contortus. This breed has been reported to be resistant to gastrointestinal parasite infection, hence it is considered an invaluable resource to study associations between host genetics and resistance. The aim of this study was to identify polymorphisms strongly associated with host resistance in a double backcross population derived from Red Maasai and Dorper sheep using a SNP-based GWAS analysis. The animals that were genotyped represented the most resistant and susceptible individuals based on the tails of phenotypic distribution (10% each) for average faecal egg counts (AVFEC). AVFEC, packed cell volume (AVPCV), and live weight (AVLWT) were adjusted for fixed effects and co-variables, and an association analysis was run using EMMAX. Revised significance levels were calculated using 100,000 permutation tests. The top five significant SNP markers with - log10 p-values >3.794 were observed on five different chromosomes for AVFEC, and BLUPPf90/PostGSf90 results confirmed EMMAX significant regions for this trait. One of these regions included a cluster of significant SNP on chromosome (Chr) 6 not in linkage disequilibrium to each other. This genomic location contains annotated genes involved in cytokine signalling, haemostasis and mucus biosynthesis. Only one association detected on Chr 7 was significant for both AVPCV and AVLWT. The results generated here reveal candidate immune variants for genes involved in differential response to infection and provide additional SNP marker information that has potential to aid selection of resistance to gastrointestinal parasites in sheep of a similar genetic background to the double backcross population. PLOS
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spelling CGSpace724262024-05-01T08:15:40Z Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population Benavides, M.V. Sonstegard, T.S. Kemp, Stephen J. Mugambi, J.M.M. Gibson, John P. Baker, R.L. Hanotte, Olivier H. Marshall, Karen Tassell, C. van animal health genetics breeds Gastrointestinal (GI) parasitic infection is the main health constraint for small ruminant production, causing loss of weight and/or death. Red Maasai sheep have adapted to a tropical environment where extreme parasite exposure is a constant, especially with highly pathogenic Haemonchus contortus. This breed has been reported to be resistant to gastrointestinal parasite infection, hence it is considered an invaluable resource to study associations between host genetics and resistance. The aim of this study was to identify polymorphisms strongly associated with host resistance in a double backcross population derived from Red Maasai and Dorper sheep using a SNP-based GWAS analysis. The animals that were genotyped represented the most resistant and susceptible individuals based on the tails of phenotypic distribution (10% each) for average faecal egg counts (AVFEC). AVFEC, packed cell volume (AVPCV), and live weight (AVLWT) were adjusted for fixed effects and co-variables, and an association analysis was run using EMMAX. Revised significance levels were calculated using 100,000 permutation tests. The top five significant SNP markers with - log10 p-values >3.794 were observed on five different chromosomes for AVFEC, and BLUPPf90/PostGSf90 results confirmed EMMAX significant regions for this trait. One of these regions included a cluster of significant SNP on chromosome (Chr) 6 not in linkage disequilibrium to each other. This genomic location contains annotated genes involved in cytokine signalling, haemostasis and mucus biosynthesis. Only one association detected on Chr 7 was significant for both AVPCV and AVLWT. The results generated here reveal candidate immune variants for genes involved in differential response to infection and provide additional SNP marker information that has potential to aid selection of resistance to gastrointestinal parasites in sheep of a similar genetic background to the double backcross population. PLOS 2015-04-15 2016-03-03T08:23:27Z 2016-03-03T08:23:27Z Journal Article https://hdl.handle.net/10568/72426 en Open Access Public Library of Science Benavides, M.V., Sonstegard, T.S., Kemp, S., Mugambi, J.M.M., Gibson, J.P., Baker, R.L., Hanotte, O., Marshall, K. and Van Tassell, C. 2015. Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population. PLoS One.
spellingShingle animal health
genetics
breeds
Benavides, M.V.
Sonstegard, T.S.
Kemp, Stephen J.
Mugambi, J.M.M.
Gibson, John P.
Baker, R.L.
Hanotte, Olivier H.
Marshall, Karen
Tassell, C. van
Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title_full Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title_fullStr Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title_full_unstemmed Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title_short Identification of novel loci associated with gastrointestinal parasite resistance in a red Maasai x Dorper backcross population
title_sort identification of novel loci associated with gastrointestinal parasite resistance in a red maasai x dorper backcross population
topic animal health
genetics
breeds
url https://hdl.handle.net/10568/72426
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