GPIHBP1 and hypertriglyceridemia: Studies of Gpihbp1−/Gpihbp1− knock out mice have shown that GPIHBP1-deficiency causes severe hypertriglyceridemia with very high plasma triglyceride levels of 2,000–5,000 mg/dl (Beigneux et al. 2007; Young et al. 2007).