APOC2 and Other metabolic disease: It is a rare autosomal recessive metabolic disorder originated from the variants of lipoprotein lipase gene, and previous studies have demonstrated that most cases with severe hyperlipidemia are closely related to the variants of some key genes for lipolysis, such as <i>LPL, APOC2, APOA5, LMF1</i>, and <i>GPIHBP1</i>.