MONDO_0018637 (familial chylomicronemia syndrome) is a rare autosomal recessive disease characterized by the buildup in the blood of fat particles called chylomicrons (chylomicronemia), severe hypertriglyceridemia, and the risk of recurrent and potentially fatal pancreatitis and other complications. It is caused by mutations in the gene encoding LPL or, less frequently, by mutations in genes encoding other proteins necessary for LPL function.