Figure 1. Dot plot of a cryptic simple sequence. (a) Dot plot using the partial human coagulation factor IX (F9) coagulation factor IX gene. Only identities of at least 75% in an 8-base-pair window are shown. (b) Alignment of a region off the diagonal that shows sequence similarity.

Figure 2. Microsatellite nomenclature. The uninterrupted microsatellite consists of a perfect repetition of CT di-nucleotides, the imperfect microsatellite has a C substituted by a A, the interrupted microsatellite has an insertion of three As, which interrupt the CT repeat, the composite repeat consists of two different juxtaposed repeats.

Figure 3. Model of DNA replication slippage adding (left) or removing (right) one repeat unit. (1) First round of DNA replication. (2) DNA slippage, causing one repeat unit to loop out; the dashed arrow indicates the direction of DNA slippage. (3) DNA synthesis continues without repair of the loop. (4) Second round of DNA replication leads to the addition or deletion of one repeat unit in one of the strands.