Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học quốc tế đề tài: Combined detection and introgression of QTL in outbred populations | Yazdi et al. Genetics Selection Evolution 2010 42 16 http content 42 1 16 GSE Ge n et i cs Selection Evolution RESEARCH Open Access Combined detection and introgression of QTL in outbred populations M Hossein Yazdi 1 Anna KSonesson2 John A Woolliams3 and Theodorus HE Meuwissen1 Abstract Background Detecting a QTL is only the first step in genetic improvement programs. When a QTL with desirable characteristics is found . in a wild or unimproved population it may be interesting to introgress the detected QTL into the commercial population. One approach to shorten the time needed for introgression is to combine both QTL identification and introgression into a single step. This combines the strengths of fine mapping and backcrossing and paves the way for introgression of desirable but unknown QTL into recipient animal and plant lines. Methods The method consisting in combining QTL mapping and gene introgression has been extended from inbred to outbred populations in which QTL allele frequencies vary both in recipient and donor lines in different scenarios and for which polygenic effects are included in order to model background genes. The effectiveness of the combined QTL detection and introgression procedure was evaluated by simulation through four backcross generations. Results The allele substitution effect is underestimated when the favourable QTL allele is not fixed in the donor line. This underestimation is proportional to the frequency differences of the favourable QTL allele between the lines. In most scenarios the estimates of the QTL location are unbiased and accurate. The retained donor chromosome segment and linkage drag are similar to expected values from other published studies. Conclusions In general our results show that it is possible to combine QTL detection and introgression even in outbred species. Separating QTL mapping and introgression processes is often thought to be longer and more costly. However using a combined process
