The model is also consistent with data from both LQT3 and BrS mutations in the C‐terminal domain of the NaV1.5 α‐subunit that probably lie at the interface for NaV1.5 with the C‐terminal intracellular region of β1 (An et al., 1998; Makita et al., 2000). This evidence concerns the gene SCN5A and long QT syndrome 3.