The association between such risk factors and the lower levels of neprilysin in the general population may be explained by the down-regulation of neprilysin in this setting to counteract impaired vasomotion, while in the setting of HF, high levels of neprilysin, upregulated by the increase of natriuretic peptides levels, are associated with detrimental effects which may be prevented by its inhibition [12]. The gene discussed is MME; the disease is hydrops fetalis.