Figure 2

Models explaining the duplication process of NBS-LRR genes. In Model 1, the tandem duplication occurred prior to the recent duplication. In Model 2, the ancient duplication event occurred first, the recent duplication event copied a gene or region to another chromosome, and the tandem duplication occurred independently. In the Mixed Model, the tandem duplication occurred prior to the recent duplication and the independent tandem duplication occurred again after the recent duplication. A bar graph of Ks values between recent duplication regions is shown in the right column of the figure. ID 10176678 was matched with Model 1, where tandem duplication occurred prior to the recent duplication. ID 18934088 was matched with Model 2, where an ancient duplication occurred first, followed by a recent duplication and then tandem duplication. ID 18159398 was matched with the Mixed Model; the tandem duplication of Group 3 on chromosome 13 occurred first and the recent duplication followed prior to the independent tandem duplication of Groups 1 and 2, which occurred on chromosomes 13 and 15.