ITPR2, for which three SNPs were significant, is expressed widely in myocytes, and expression of these receptors is altered in heart failure, which suggests that the signaling mechanism associated with ITPR2 is responsible for critical cardiac functionality for contractility through the regulation of Ca2+ channels that are important in the maintenance of vascular tone (Kockskamper et al. 2008). This evidence concerns the gene CA2 and heart failure.