RYR2 and heart failure: First, regarding whether there is a correlation between sub-conductance activity and the amount of FKBP bound to RyR2 (Galfré et al., 2012; Lam et al., 1995) and, second, whether the binding of FKBPs to RyR2 is generally altered as a result of disease-associated mutations in RyR2 (Lehnart et al., 2004; Meli et al., 2011) or heart failure (Marx and Marks, 2002).