The R2597 duplication is a TD in the chromosome.

<p>(A) Predicted R2597 chromosome structure. A–E, duplicated regions; X/Z, flanks; Y, <i>codY</i>; R₁/R₂ flanking IS<i>861</i>; R2/1, predicted hybrid IS<i>861</i>. PCR detected the predicted junction in R2597. Green rectangle, TD junction; black rectangle, sequence represented in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003819#pgen-1003819-g001" target="_blank">Figure 1B</a>. (B) Representation of the R_2/1 hybrid at the TD junction in R2597 identified by sequencing. Mismatches are represented by vertical black lines, extending either above (R₁) or below (R₂) the diagram. Horizontal green line represents region within which R₁ and R₂ recombined. Green arrows represent limits of recombination between R₁ and R_2. (C) PFGE analysis of R2597. Open arrows, restriction fragments predicted in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003819#pgen.1003819.s006" target="_blank">Table S1</a>. Red arrowhead, merodiploid-specific fragment revealed by hybridization. Although the lanes shown were part of the same initial gel/membrane, lanes present between them have been removed to simplify comparison between lanes.