CTRB2 and exocrine pancreatic carcinoma: Another set of fusions that are less easily explained involve those we found only in normal pancreas and pancreatic carcinoma (Figures 6 and S6), involving various pairwise combination of CPA1, CPA2, CLPS, CELA2A, CELA3A, CTRB1, CTRB2, and CTRC (e.g., CELA3A::CPA2, CELA3B::CELA2A, and CELA3A::CELA2A) fused to generate in-frame fusion products.