This is exemplified by clinical pathological conditions following ischaemic insult (Rohr, 2004), atrial fibrillation (Chaldoupi et al., 2009) and experimental platforms with loss-of-function, Cx43 (Eloff et al., 2001; Gutstein et al., 2001) or Cx40, genetic modifications (Hagendorff et al., 1999; Bagwe et al., 2005). The gene discussed is GJA1; the disease is atrial fibrillation.