These genes have been rarely studied in cardiac aging, and only a small number of studies have confirmed changes in the expression of CP and penk in aging tissues.[34,35] PNPLA2 has been recognized as a vital triglyceride hydrolase in lipid droplets/adiposome turnover in mammalian cells.[36] As previously mentioned, lipid metabolism disorders are closely related to cardiac aging, therefore PNPLA2 should be considered as an important gene associated with cardiac aging. The gene discussed is PENK; the disease is Disorder of lipid metabolism.