Single nucleotide polymorphism in coronary artery disease as in-stent restenosis risk factor

In-stent restenosis (ISR) is recently challenging complication of coronary stent implantation in both stable coronary artery disease (CAD) and acute coronary syndrome (ACS). Since coronaroplasty is not only done using balloons, the stent era has pushed invasive cardiology further also to the new era of procedures’ complications, including drawback due to ISR [1]. Single nucleotide polymorphism (SNP) is a genetic variation leading to change in one specifi c location causing signifi cant change in coded protein. It leads to over 90% of genetic variation in human species and may vary among different population groups [2]. Linkage between ISR and SNPs may answer the question why in the era of modern cardiology we still need to struggle with repeating invasive procedures. The next question is whether we could isolate these patients and support them with genetic screening and increased number of control visits. Many factors contribute to CAD, but only some have impact on ISR. SNPs would be a nice marker to examine before we implant stents in stable CAD subject. SNPs of genes coding angiotensin converting enzyme (ACE – rs1799752), angiotensinogen (rs699), basic fi broblast growth factor (bFGF – rs308395) and renin (rs5705) lead to CAD, but not to ISR [3–5]. In CAD and ISR SNPs proven correlations exist for genes coding transforming growth factor beta 1 (TGF-β1 – rs1800470), platelet-derived growth factor beta (PDGFB – rs2285094), vascular endothelial growth factor A (VEGF-A – rs699947) and connexin 37 (CX-37 – rs1764391) [3, 6, 7]. ISR was found also among patients with CAD and genetic variant of interleukin 18 (IL-18 – rs187238) -137G/G which has not been proven for -137G/C and -137C/C variants obtained from non-CAD controls [8]. Also endothelial nitric oxide synthase (eNOS – rs1799983) was suspected to contribute to susceptibility of ISR in CAD patients its 298G/T variant was investigated together with glutation peroxidase (GPx-1 rs1050450) 599C/T SNP and both of them were found to play role in ISR signifi cantly [9]. eNOS CAD patients studied in other project were proven that carriers of the 298Asp allele of the eNOS (rs1799983) polymorphism showed a higher frequency of restenosis compared to 298Glu homozygotes [10]. Also cyclin-dependent kinase inhibitor p27 ABSTRACT