Abstract:
Background: Severe hypertriglyceridemia often results from a combination of primary and secondary causes. Primary causes are genetic defects in triglyceride hydrolysis. We examined the genetic variants of the LPL gene, which encodes for lipoprotein lipase, a key enzyme in triglyceride hydrolysis in patients with severe hypertriglyceridemia. Methods: Patients with fasting triglyceride level ≥ 886 mg/dl (10 mM) on at least 2 occasions (N=90) and control subjects (N=100) who had fasting triglyceride level < 150 mg/dl without any lipid-lowering agent, matched for age and sex, were recruited. LPL variants were determined using standard DNA sequencing method. Results: In 90 cases of severe hypertriglyceridemia, two-thirds were male with the median age of 48 years (IQR: 40-56 years). Four non-synonymous variants of LPL in 10 patients were found in cases but none in control (p=0.002). The Ala98Thr and the Leu279Val variants have previously been shown to be associated with hypertriglyceridemia, whereas the Arg270Gly and the Arg432Thr variants are novel. Interestingly, the Ser474X polymorphism, which was previously reported to be a protective variant, was also found in 3 percent of hypertriglyceridemia versus sixteen percent in the control group (p=0.004). Conclusion: Four non-synonymous LPL variants including two novel variants (the Arg270Gly and the Arg432Thr) were found in Thai patients. These variants may predispose them to severe hypertriglyceridemia.