Relationship of lipoprotein lipase gene variants and fasting triglyceride levels in a pediatric population: The CASPIAN-III study

Abstract

Background. Lipoprotein lipase (LPL) is one of the major enzymes responsible for the hydrolysis of triglyceride (TG)-rich lipoprotein. The effects of LPL polymorphisms on serum TG are inconsistent among different populations. Objectives. This study aims to assess the TG serum concentration and distributions of three LPL single nucleotide polymorphisms (SNPs), namely D9N, HINDIII and S447X, in a nationally representative sample of Iranian adolescents. Material and methods. We studied the associations between SNP genotypes and TG levels in a nationally representative sample of Iranian adolescents. Genotyping was performed in 750 randomly selected participants. We compared the genotypes according to different TG levels. Results. This study comprised 746 participants, with mean +/- SD age of 14.6 +/- 2.5 years. The distribution of genotypes of D9N and S447X were not significantly different according to TG levels. Regarding the HINDIII polymorphism, the distribution of GG, GT, and TT genotypes were significantly different in participants with low, borderline-high, and elevated TG (p = 0.02, 0.03, and 0.01, respectively). The mean TG was not significantly different according to the genotype distribution. Conclusions. In this study, most of the LPL gene variants were not significantly different in adolescents with normal and elevated TG, and the mean TG was not different in participants with various genotypes. As the first evidence from the pediatric population of the region of the Middle East and North Africa (MENA), these results might be used in international comparisons. Our findings might suggest that the high prevalence of hypertriglyceridemia in Iranian adolescents is more likely to be a result of lifestyle rather than genetic factors.