Tomasz Iwanicki

APOE Gene ε Polymorphism Does Not Determine Predisposition to Ischemic Stroke in Children

Ischemic stroke in children is relatively rare, but it remains an important medical problem. Previous studies on Polish children have implicated dyslipidemias as significant risk factors in stroke. To search for genetic factors associated with the disease, the possible association between apolipoprotein E gene epsilon polymorphism and childhood stroke was evaluated. The study population consisted of 243 individuals: 72 children with ischemic stroke and 100 of their biological parents and 71 children without any symptoms of stroke. The apolipoprotein E gene epsilon polymorphism was genotyped using restriction fragment length polymorphism methodology. To analyze the possible association between this polymorphism and stroke, the transmission disequilibrium test and the case-control model were used. No preferential distribution of any allele from parents to the affected children was observed. There were also no significant differences in genotype and allele distribution between patients and control subjects. Study findings did not confirm that epsilon polymorphism of the apolipoprotein E gene is a risk factor of ischemic stroke in children.

Polymorphisms of genes encoding coagulation factors II, V, VII, and XIII in relation to pediatric ischemic stroke: family-based and case-control study.

Background:The investigation of a possible association between the FII, FV, FVII, and FXIII genes polymorphisms and pediatric ischemic stroke (IS). Methods:The study group consisted of 392 individuals, including 81 children with IS, their biological parents (n=162), and 149 control children. The polymorphisms were genotyped using polymerase chain reaction-restriction fragments length polymorphism method. The relation between analyzed polymorphisms and the disease was tested by 2 independent methods: family-based association test—transmission/disequilibrium test (TDT) and classic case-control model. Results:We did not observe any preferential distribution of any analyzed allele from parents to the affected children. For the FVII gene polymorphism, there was a trend toward a higher frequency of the R allele. In a case-control model, the differences between the patients and controls in the frequency of the Q allele, Q allele carriers, and RR homozygotes lay close to the border of statistical significance (P=0.08). There were no significant differences in genotype and allele distribution between patients and controls in case of other polymorphisms. Conclusions:Analyzed polymorphisms of coagulation factors are not significant determinants of pediatric IS in the studied population; however, these findings require a confirmation in a larger group of participants.

The rs2516839 Polymorphism of the USF1 Gene May Modulate Serum Triglyceride Levels in Response to Cigarette Smoking.

Single nucleotide polymorphisms (SNPs) of the USF1 gene (upstream stimulatory factor 1) influence plasma lipid levels. This study aims to determine whether USF1 SNPs interact with traditional risk factors of atherosclerosis to increase coronary artery disease (CAD) risk. In the present study serum lipid levels and USF1 gene polymorphisms (rs2516839 and rs3737787) were determined in 470 subjects: 235 patients with premature CAD and 235 controls. A trend of increasing triglycerides (TG) levels in relation to the C allele dose of rs2516839 SNP was observed. The synergistic effect of cigarette smoking and C allele carrier state on CAD risk was also found (SIM = 2.69, p = 0.015). TG levels differentiated significantly particular genotypes in smokers (1.53 mmol/L for TT, 1.80 mmol/L for CT and 2.27 mmol/L for CC subjects). In contrast, these differences were not observed in the non-smokers subgroup (1.57 mmol/L for TT, 1.46 mmol/L for CT and 1.49 mmol/L for CC subjects). In conclusion, the rs2516839 polymorphism may modulate serum triglyceride levels in response to cigarette smoking. Carriers of the C allele seem to be particularly at risk of CAD, when exposed to cigarette smoking.

Relationship between rs854560 PON1 Gene Polymorphism and Tobacco Smoking with Coronary Artery Disease

Paraoxonase-1 (PON1) is the antioxidant marker of high-density lipoproteins protecting against atherosclerosis and coronary artery disease (CAD) phenotype. The purpose of the present study was to determine whether the PON1 gene rs854560 polymorphism (163T>A) is associated with CAD in Polish population. rs854560 was genotyped in 494 subjects: 248 patients with premature CAD and 246 blood donors as a control. We found that the risk of CAD was significantly higher in TT homozygotes than in A allele carriers (OR = 1.87, p = 0.041). The synergistic effect between the TT genotype and cigarette smoking was observed (SIM = 9.81; SI = 14.70). The relative increase in risk from interaction between factors was over 37 (RERI = 36.13). The PON1 polymorphism did not modulate the risk of CAD in response to exposure to other traditional risk factors. In conclusion, the rs854560 polymorphism may modulate the risk of CAD in response to cigarette smoking in Polish population. Carriers of TT genotype seem to be particularly at risk of CAD, when exposed to cigarette smoking.

CYP7A1 Gene Polymorphism Located in the 5′ Upstream Region Modifies the Risk of Coronary Artery Disease

Background. 7-Alpha cholesterol hydroxylase (CYP7A1), the first enzyme of classic conversion pathway leading from cholesterol to bile acids synthesis, is encoded by CYP7A1 gene. Its single nucleotide polymorphisms (SNPs) influence serum lipid levels and may be related to impaired lipid profile leading to coronary artery disease (CAD). The aim of the present study was to analyze the possible association between the rs7833904 CYP7A1 polymorphism and premature CAD. Material and Methods. Serum lipid levels and rs7833904 SNP were determined in 419 subjects: 200 patients with premature CAD and 219 age and sex matched controls. Results. The A allele carrier state was associated with CAD (OR = 1.76, 95% CI; 1.14–2.71, P = 0.014). The effect was even stronger in the male subgroups (OR = 2.16, 95% CI; 1.28–3.65, P = 0.003). There was no effect in the females. Risk factors of CAD and clinical phenotype of atherosclerosis were not associated with genotype variants of the rs7833904 SNP. Lipid profiles also did not differ significantly between individual genotypes. Conclusion. The CYP7A1 rs7833904 polymorphism may modify the risk of CAD. This effect is especially strong in male subjects. The studied polymorphism does not significantly influence serum lipid levels, in the present study.

The rs10757278 Polymorphism of the 9p21.3 Locus Is Associated with Premature Coronary Artery Disease in Polish Patients

Recently, genome-wide association studies have revealed a locus associated with coronary artery disease (CAD) and myocardial infarction, namely, 9p21.3. Its participation in the conditioning of the disease has been proven in many populations of European descent, but not yet in Slavs. Allelic variants of the rs10757278 polymorphism functionally affect the activity of the 9p21.3 locus; therefore, we conducted a study to determine whether the rs10757278 is associated with premature CAD in Polish patients. We studied 320 subjects aged 25-55 years, divided into two groups matched by sex and age: (1) patients with angiographically proven premature CAD (n=160), and (2) blood donors as a control group (n=160). The rs10757278 was genotyped using the method of fluorescently labeled allele-specific oligonucleotides. The frequency of the G allele was significantly higher in patients than in controls (58.2% vs. 42.8%, respectively, p=0.011) and was similar to the frequency of the GG homozygotes (30.6% vs. 17.5%, respectively, p=0.006). Both the GG homozygosity (odds ratio [OR]=2.08, 95% confidence interval [CI]: 1.19-3.66) as well as the G allele (OR=1.49, 95% CI: 1.08-2.07) have been associated with CAD in the analyzed population. These variants may be considered as risk factors, also in the Polish population.

Relationship between CETP gene polymorphisms with coronary artery disease in Polish population

The cholesteryl ester transfer protein (CETP) gene encodes a hydrophobic glycoprotein that plays a crucial role in the reverse transport of cholesterol. The aim of the present study was to determine whether CETP polymorphisms (rs1532624, rs247616 and rs708272) are associated with coronary artery disease (CAD) in a Polish population. Serum lipid levels and single nucleotide polymorphisms of CETP genes were determined in 494 subjects: 248 patients with premature CAD and 246 blood donors as controls. Selected polymorphisms were examined using TaqMan PCR analysis. We found that CAD risk was significantly higher for CC homozygotes and C allele carriers of the rs247616 polymorphism than for carriers with the T allele (OR 1.89, 95% CI 1.29–2.76, p = 0.001 and OR 1.51, 95% CI 1.14–1.99, p = 0.003) and likewise for the CC genotype of the rs1532624 polymorphism than for those with the A allele (OR 1.59, 95% CI 1.05–2.40, p = 0.026). Moreover, T allele carriers of the rs708272 polymorphism had significantly higher total cholesterol levels compared to CC homozygotes (p < 0.05) in the healthy controls. We also observed an allelic pattern, C(rs2477616)C(rs708272)C(rs1532624), which increased susceptibility to CAD by 43% (OR = 1.43, 95% CI 1.10–1.85, p = 0.006). In conclusion, the rs247616 and rs1532624 polymorphisms of CETP may modulate the risk of CAD in Polish population.

Analysis of selected promoter polymorphisms and haplotypes of the CYBA gene encoding the p22phox, subunit of NADPH oxidases, in patients with coronary artery disease

Abstract The p22phox is a critical component of vascular NADPH oxidases and is encoded by the CYBA gene. It was shown that functionally relevant polymorphisms of the CYBA gene −930A > G, −852C > G, −675A > T, −536C > T, 214C > T (previously described as 242C > T), *24A > G (previously described as 640A > G), and *49A > G modulate generation of reactive oxygen species (ROS). To analyse whether the CYBA gene polymorphisms −852C > G, −675A > T, and −536C > T were associated with coronary artery disease (CAD), and to designate haplotype blocks. Four hundred and ninety subjects: 245 patients with CAD and 245 age and sex-matched controls. The polymorphisms were genotyped using the PCR-RFLP method and the TagMan® Pre-designed SNP Genotyping Assay. The analysed polymorphisms do not form haplotype blocks. Case–control study revealed that the −930 G/-675T and −930G/*49G diplotypes were a CAD risk factor. The 675T/*49G diplotype can modulate CAD risk in women. The protective effect reducing CAD risk in women was related to the −930A/−675T and −930A/*49A diplotypes. Carrier state of the −852C allele (−852C > G) was associated with multivessel stenosis while the CC genotype of the −536C > T polymorphism was more frequent in patients with peripheral artery disease. Hypercholesterolemic, cigarette smokers had an increased risk of CAD, especially C − 852 allele (−852C > G) carriers (SIM = 3.54; odds ratios (OR) = 10.01, p < 0.000). The CYBA gene polymorphisms modulate the risk of CAD but do not form a haplotype blocks.

The rs10757278 Polymorphism of the 9p21.3 Locus in Children with Arterial Ischemic Stroke: A Family-Based and Case-Control Study

BACKGROUND The association of 9p21.3 locus single nucleotide polymorphisms with arterial ischemic stroke in adults was demonstrated in many studies, but there are no studies in pediatric arterial ischemic stroke patients. We investigated whether the 9p21.3 locus polymorphism, namely rs10757278, is associated with the arterial ischemic stroke risk in children. METHODS The study group consisted of 335 individuals: 80 children with arterial ischemic stroke, their biological parents (n = 122), and 133 children (age and sex matched) without any symptoms of arterial ischemic stroke as a control group. The rs10757278 polymorphism was genotyped using the TaqMan® Pre-designed SNP Genotyping Assay (Applied Biosystems). Two different study design models were used: family-based association test (transmission-disequilibrium test) and case-control model. RESULTS There were no statistically significant differences in the distribution of genotypes and alleles of the rs10757278 polymorphism between groups of children with arterial ischemic stroke and controls. The frequency of both transmitted alleles in transmission-disequilibrium test analysis was identical (50%). The A allele carrier state (AA+AG genotype) was more frequent in arterial ischemic stroke children with hemiparesis than in patients without this symptom (94.5% versus 68.0%, P = .004). CONCLUSIONS There is no evidence to consider the 9p21.3 locus polymorphism as a risk factor for childhood arterial ischemic stroke.

The CYBA Gene 49A>G Polymorphism (rs7195830) Is Associated with Hypertension in Patients with Coronary Artery Disease

Purpose. Single nucleotide polymorphisms of the CYBA gene may modify the risk of coronary artery disease (CAD). The aim of the present study was to investigate whether the ⁎49A>G (rs7195830) polymorphism is associated with CAD. Materials and Methods. CYBA gene ⁎49A>G polymorphism was determined in 481 subjects: 242 patients with premature CAD and 239 age and sex matched controls using the fluorescently labeled allele-specific oligonucleotides method. Results. The frequency of the ⁎49G allele carrier state was significantly higher in patients than in controls (84.8% versus 76.6%, resp., P = 0.020), as well as the frequency of the ⁎49G allele (62.2% versus 54.0%, P = 0.009). Both factors were associated with CAD in the analyzed population (OR = 1.70, 95% CI: 1.04–2.76 for GG+AG versus AA and OR = 1.40, 95% CI: 1.08–1.83 for ⁎49G versus  ⁎49A). Carrier state of the ⁎49G allele was a stronger and independent risk factor for CAD among women (OR = 4.35, 95% CI: 1.50–13.20, P = 0.002), as well as the ⁎49G allele (OR = 2.25, 95% CI: 1.34–3.77, P = 0.001). The ⁎49G allele carrier state was also associated with left ventricular hypertrophy in patients with coronary artery disease (P = 0.015). Conclusion. The CYBA gene ⁎49A>G polymorphism modifies the risk of coronary artery disease.