Figure 2.

Illustration of two successive sets of nodes that contain SNPs. The sequences within all the nodes in the second column and the sequences within all the nodes on the fourth column must be of the same length in order to contain SNPs. Note that there can be more than one SNP within each of these columns, and all these nodes will be merged into a single node. Other incoming edges that go into the starting node and other outgoing edges that go out of the final node are allowed.