Effect of apolipoprotein B-100 EcoRI polymorphism on serum lipids and insulin resistance in obese children

Abstract

Objective: The aim of this work was to evaluate the role of apolipoprotein B-100 (ApoB-100) Eco RI gene polymorphism on serum lipid parameters and BMI in obese children and its possible relationship with insulin resistance. This is the first study in Egypt to determine possible relationships of these parameters. Background: ApoB-100 is a large, amphipathic glycoprotein playing a central role in human lipoprotein metabolism and is required for very low-density lipoprotein production in the liver. ApoB-100 is also the ligand for low-density lipoprotein-receptor-mediated endocytosis of low-density lipoprotein particles. There are several known ApoB-100 polymorphisms that were proven to cause obesity, hyperlipidemia, and cardiovascular diseases. Three common polymorphisms were found, MspI, XbaI, and Eco RI (exon 26), which have been associated with variation in lipid levels. Materials and methods: BMI was calculated, fasting serum lipids were assayed by routine techniques on Synchron systems, serum fasting insulin was assayed by ELISA technique, HOMA-IR was calculated, DNA was extracted from whole blood, amplified, and then ApoB-100 Eco RI polymorphism was assayed using PCR-RFLP. Results: The results of this study revealed that there was a significant statistical difference in BMI, lipid profile, insulin, and insulin resistance between positive Eco RI and negative Eco RI polymorphisms, and hence there was a direct positive relationship between ApoB-100 Eco RI polymorphism and all studied parameters. Results were collected, tabulated, and statistically analyzed using the statistical package for the social sciences (SPSS, version 11). Two types of statistics were performed: the Mann–Whitney U-test and Pearson's correlation. Conclusion: This study revealed a great association between ApoB-100 Eco RI gene polymorphism and atherogenic hyperlipidemia and insulin resistance in obese pediatric patients.