With respect to the notion that genetic factors contribute greatly to the risk and development of CHF [11], polymorphisms in HRH2, HRH3, DAO, and HNMT genes are likely to be also associated with CHF risk, which, however, is still uninvestigated despite the fact that the roles of some of these proteins in CHF were intensively investigated. This evidence concerns the gene HNMT and congestive heart failure.