Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: A further look at quantitative trait loci affecting growth and fatness in a cross between Meishan and Large White pig populations | Genet. Sel. Evol. 34 2002 193-210 INRA EDP Sciences 2002 DOI gse 2002003 193 Original article A further look at quantitative trait loci affecting growth and fatness in a cross between Meishan and Large White pig populations Raquel QUINTANILLAa Denis MILANb Jean-Pierre BIDANELa a Station de génétique quantitative et appliquée Institut national de la recherche agronomique 78352 Jouy-en-Josas Cedex France b Laboratoire de génétique cellulaire Institut national de la recherche agronomique 31326 Castanet Tolosan Cedex France Received 23 April 2001 accepted 15 October 2001 Abstract - A detailed quantitative trait locus QTL analysis of growth and fatness data from a three generation experimental cross between Large White LW and Meishan MS pig breeds was carried out to search for sex X QTL interactions imprinting effects and multiple linked QTLs. A total of 530 F2 males and 573 F2 females issued from 6 F1 boars and 23 F1 sows were typed for a total of 137 markers covering the entire porcine genome. Nine growth traits and three backfat thickness measurements were analysed. All analyses were performed using line cross regression procedures. A QTL with sex-specific expression was revealed in the proximal region of chromosome 8 although some confusion between herd and sex effects could not be discarded. This previously undetected QTL affected male growth during the fattening period with a favourable additive effect of the LW allele. The analyses also revealed the presence of two linked QTLs segregating on chromosome 1 affecting growth traits during the post-weaning period. The first QTL previously detected using a single QTL model was located at the end of the q arm of chromosome 1 and had a favourable MS allele. The second QTL had a favourable LW allele and was located in the proximal extremity of the q arm of chromosome 1. Suggestive genomic imprinting was found in the distal region of chromosome 9 affecting growth during the fattening period. pig growth sex-QTL .