Genetic polymorphism of S447X lipoprotein lipase (LPL) and the susceptibility to hypertension.

INTRODUCTION

Lipoprotein lipase (LPL) is a rate-limiting enzyme responsible for the hydrolysis of triacylglycerol-rich lipoproteins releasing monoglycerides and free fatty acids, which are taken up by skeletal muscles and adipose tissue. S447X polymorphism in exon 9 of LPL gene on chromosome 8 p22 results from replacement of serine amino acid with a stop codon creating a restriction site. It has been hypothesized that the more common SS genotype is associated with a lower LPL activity compared with the infrequent SX/XX genotype.

OBJECTIVES

To investigate the effect of genetic polymorphism of LPL S447X in blood pressure and its atherogenic phenotype.

MATERIALS AND

METHODS

S447X variant genotype of LPL were determined by polymerase reaction (PCR) restriction fragment length polymorphism assay in 50 hypertensive patients and 50 normotensive as a control group. Anthropometric measurements and serum lipoproteins were also determined in both groups.

RESULTS

The frequency of (SS) genotype was 78% in hypertensive group compared to 66% in normotensive group. Carrier of (SS) genotype were at higher risk of developing hypertension (OR, 1.8; 95% CI, 0.8-4.4) when compared with carrier of other genotypes. Furthermore, they showed atherogenic phenotype manifested by central obesity and dyslipidemia. Odds ratios were 1.8 and 2.6, respectively.

CONCLUSION

It was found that carriers of (SS) genotype were at high risk of developing hypertension.