Regressão aleatória na detecção de QTL para características de crescimento de suínos

• Autor(a) principal: Pinheiro, Valéria Rosado
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4049
• topic: Regressão aleatória; QTL; Suínos; Curva de crescimento; Random regression; QTL; Swine; Growth traits; CNPQ::CIENCIAS AGRARIAS

Many studies are focused on the search for QTL(quantitative trait loci) that affects growth traits in swine, and almost all studies have found QTL with significant effects. However, most of these studies use information related to the body weight on specific ages or average weight gain. Thus, it becomes interesting to evaluate all the growth information with the focus on longitudinal data simultaneously. This study aims to use random regression models (RRM) in order to detect QTL (quantitative trait loci) for growth traits in swine from a population F2 Piau x Commercial. To this end, it was considered a RRM with random polygenic effects, permanent environment and QTL, being the covariance matrix associated with the latter known as IBD (identical-by-descent). The presence of a significant QTL was found by likelihood ratio test considering the model described above as being the complete and this same without the QTL effect as null model. Comparisons between these models were made at the positions of the markers (6 microsatellite markers) and at positions between markers. In the position with greater evidence of QTL effect was calculated the heritability and the genetic polygenic and QTL values for body weight throughout the growth period studied. The results showed a significant effect of QTL at position 65 of chromosome 7.