Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Genetic analysis of a divergent selection for resistance to Rous sarcomas in chickens | Genet. Sel. Evol. 36 2004 65-81 INRA EDP Sciences 2004 DOI gse 2003051 65 Original article Genetic analysis of a divergent selection for resistance to Rous sarcomas in chickens Marie-Helene Pinard-VAN DER LAANa Denis SouBiEuxb Laurence MEratc Daniele BouRETd Gillette LuNEAud Ginette DAMBRiNEb Pierrick THORAVALb a UMR Genetique et diversite animales Institut national de la recherche agronomique 78352 Jouy-en-Josas Cedex France b Unite BioAgresseurs Sante Environnement Institut national de la recherche agronomique 37380 Nouzilly France c Station de pathologie aviaire et parasitologie Institut national de la recherche agronomique 37380 Nouzilly France d Domaine du Magneraud St-Pierre-d Amilly Institut national de la recherche agronomique bp 52 17700 Surgeres France Received 9 December 2002 accepted 27 August 2003 Abstract - Selection for disease resistance related traits is a tool of choice for evidencing and exploring genetic variability and studying underlying resistance mechanisms. In this framework chickens originating from a base population homozygote for the B19 major histocompatibility complex MHC were divergently selected for either progression or regression of tumors induced at 4 weeks of age by a SR-D strain of Rous sarcoma virus RSV . The first generation of selection was based on a progeny test and subsequent selections were performed on full-sibs. Data of 18 generations including a total of 2010 birds measured were analyzed for the tumor profile index TPI a synthetic criterion of resistance derived from recording the volume of the tumors and mortality. Response to selection and heritability of TPI were estimated using a restricted maximum likelihood method with an animal model. Significant progress was shown in both directions the lines differing significantly for TPI and mortality becoming null in the regressor line. Heritability of TPI was estimated as and within the progressor and regressor lines respectively and .