Quantitative analysis of parent-of-origin effect in reproductive and morphological selection criteria in the Pura Raza Española horse

It is generally assumed that parents make a genetically equal contribution to their offspring, but this assumption might not always hold. This is because the expres-sion of a gene can be blocked by methylation during gametogenesis, and the de-gree of methylation can depend on the origin of the paren...

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Detalles Bibliográficos
Autores: Perdomo González, Davinia Isabel, Varona, L., Molina, Antonio, Laseca, Nora, Valera Córdoba, María Mercedes
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/156563
Acceso en línea:https://hdl.handle.net/11441/156563
https://doi.org/10.1111/jbg.12811
Access Level:acceso abierto
Palabra clave:Horse
imprinting
morphological traits
parent-of-origin effect
reproductive traits
Descripción
Sumario:It is generally assumed that parents make a genetically equal contribution to their offspring, but this assumption might not always hold. This is because the expres-sion of a gene can be blocked by methylation during gametogenesis, and the de-gree of methylation can depend on the origin of the parental gene (imprinting) or by preferential management associated with genetic merit. The first conse-quences of this for quantitative genetics is that the mean phenotypes of recipro-cal heterozygotes need no longer be the same, as would be expected according to Mendelian heritage. We analysed three mare reproductive traits (reproduc-tive efficiency, age at first foaling and foaling number) and three morphological traits (height at withers, thoracic circumference, and scapula- ischial length) in the Pura Raza Española (PRE) horse population, which possesses a deep and reli-able pedigree, making it a perfect breed for analysing the quantitative effect of parent- of- origin. The number of animals analysed ranged from 44,038 to 144,191, all of them with both parents known. The model comparison between a model without parent- of- origin effects and three different models with parent- of- origin effects revealed that both maternal and paternal gametic effects influence all the analysed traits. The maternal gametic effect had a higher influence on most traits, accounting for between 3% and 11% of the total phenotypic variance, while the paternal gametic effect accounted for a higher proportion of variance in one trait, age at first foaling (4%). As expected, the Pearson's correlations between additive breeding values of models that consider parent- of- origin and that do not consider parent- of- origin were very high; however, the percentage of coincident animals slightly decreases when comparing animals with the highest estimated breed-ing values. Ultimately, this work demonstrates that parent- of- origin effects exist in horse gene transmission from a quantitative point of view. Additionally, in-cluding an estimate of the parent- of- origin effect within the PRE horse breeding program could be a great tool for a better parent's selection and that could be of interest for breeders, as this value will determine whether the animals acquire genetic categories and are much more highly valued.