Inhibiting AC6 shares none of the salutary features of inhibiting AC5, as summarized in this review, with one exception; that is, there are two divergent reports on the regulation of cardiomyopathy by the AC6 KO model: one which claims it is protective [128], as we demonstrated for the AC5 KO [1, 2], and another with the opposite conclusions; that is, AC6 KO results in more severe cardiomyopathy [129]. This evidence concerns the gene ADCY5 and cardiomyopathy.