Investigation of relationship between a non-coding rs599839 variant associated with sortilin (Sort1) gene region and lipoprotein subfractions in patients with coronary artery disease

In this study, the relationships between Sort1 gene expression and lipoprotein subclasses and CAD were investigated. In addition, the rs599839 polymorphism which is located in the same locus withSort1 gene and its effects on Sort1 gene expression was identified. The study population included 162 patients with various levels of vascular occlusion detected by the angiography result and 49 healthy subjects.Lipid profiles (TAG, TK, LDL, HDL), serum apolipoprotein (ApoA, ApoB and ApoE) levels and CRP level were measured by autoanalyzer in routine biochemistry laboratory. Lipoprotein subclasses were analyzed by the Quantimetrix lipoprinting system. The Sort1 gene expression level was determined by qRT-PCR using Human Sortilin TaqMan Gene Expression Assays. Genomic DNA was extracted from whole blood and the genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to detect rs599839 polymorphism. Expression of the Sort1 gene was found significantly increased (p <0,001) in the CAD group compared to the control group. However, no significant differences (p> 0,05) were identified in Sort1 gene expression between variant allele groups of rs599839. When the lipoprotein subclasses were evaluated in the study groups; atherogenic subfractions (SdLDL-K and SHDL) were found to be statistically higher in CAD than control group (p <0,01). Patients with CAD had significantly higher levels of plasma atherogenic index (AIP), TG / HDL-C, Apo B / Apo AI, SdLDL / LbLDL and low LDL-C / Apo B levels compared to the controls (p <0,05). In conclusion, it has been found that Sort1 gene expression particularly has a linear relationship with both the atherogenic LDL phenotype and CAD.