The expression patterns of early cardiac markers, like NKX2.5 (ref. 29), and the signalling molecules previously implicated in their induction (BMP2/4/7 (ref. 22), FGF8 (ref. 34) and CRESCENT (ref. 49)) indicate that initial signals act at an early stage of cardiogenesis (HH4-6, Fig. 5a) before the AIP forms. Here, BMP2 is linked to autoimmune pancreatitis.