Figure 2 Detection of t(11;18)(q21;q21). (A) Four examples of products of reverse transcription polymerase chain reaction of the API2‐MALT1 fusion from formalin fixed paraffin embedded tissues, run on an agarose gel. The left lane is the size ladder. G6PD serves as a control for RNA quality. P‐AS3, 2, and 1 are different primer sets designed to amplify DNA across various possible AP12‐MALT‐1 fusion positions. The bold arrows point to the main amplified AP12‐MALT1 fusion product. The small arrowhead shows an alternative splicing variant of the API2‐MALT1 transcript in example 4. (B) Example of interphase fluorescence in situ hybridisation (FISH) with API2/MALT1 dual colour, dual fusion translocation probes. Arrowheads indicate colocalisation of the red (MALT1) and green (API2) signals.