Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học quốc tế đề tài: Fine mapping and replication of QTL in outbred chicken advanced intercross lines | Besnier et al. Genetics Selection Evolution 2011 43 3 http content 43 1 3 GSE Ge n et i cs Selection Evolution RESEARCH Open Access Fine mapping and replication of QTL in outbred chicken advanced intercross lines 1 2 3 1 4 Francois Besnier Per Wahlberg Lars Ronnegard Weronica Ek Leif Andersson Paul B Siegel Orjan Carlborg1 5 Abstract Background Linkage mapping is used to identify genomic regions affecting the expression of complex traits. However when experimental crosses such as F2 populations or backcrosses are used to map regions containing a Quantitative Trait Locus QTL the size of the regions identified remains quite large . 10 or more Mb. Thus other experimental strategies are needed to refine the QTL locations. Advanced Intercross Lines AIL are produced by repeated intercrossing of F2 animals and successive generations which decrease linkage disequilibrium in a controlled manner. Although this approach is seen as promising both to replicate QTL analyses and fine-map QTL only a few AIL datasets all originating from inbred founders have been reported in the literature. Methods We have produced a nine-generation AIL pedigree n 1529 from two outbred chicken lines divergently selected for body weight at eight weeks of age. All animals were weighed at eight weeks of age and genotyped for SNP located in nine genomic regions where significant or suggestive QTL had previously been detected in the F2 population. In parallel we have developed a novel strategy to analyse the data that uses both genotype and pedigree information of all AIL individuals to replicate the detection of and fine-map QTL affecting juvenile body weight. Results Five of the nine QTL detected with the original F2 population were confirmed and fine-mapped with the AIL while for the remaining four only suggestive evidence of their existence was obtained. All original QTL were confirmed as a single locus except for one which split into two linked QTL. Conclusions Our results
