Association Of Polymorphisms Of CYP4F2,CYP4A11 And LTC4S Gene With Ischemic Stroke

Effect of Polymorphisms of CYP4F2,CYP4A11 and LTC4S Gene on Ischemic StrokeObjectiveCerebrovascular disease(CVD) is one of the three major causes of death, and is harmful to human health. Ischemic stroke(IS) of incidence of cerebrovascular disease accounted for 80%.IS is a heterogeneous multifactorial disorder. In addition to conventional risk factors such as hypertension, diabetes mellitus, and smoking, evidence from animals and clinical and epidemiological studies have repeatedly supported the likelihood of a genetic contribution to CI susceptibility. Epidemiological data provide substantial evidence for a genetic component to the disorder. Identifying accurately its genetic determinants is a key issue in order to improve diagnosis and treatment strategies and to reduce stroke's huge public health burden.Arachidonic acid (AA) is the most abundant substances in the human body which is one of the important precursors of cardiovascular active substances. It has been reported that 20-hydroxyeicosatetraenoic acid (HETE) plays an important role in the pathogenesis of ischemic stroke.20-HETE is a metabolite of arachidonic acid (AA) generated by the CYP4F2 and CYP4A11 subfamily of cytochrome P450 (CYP450) and plays a significant role in the regulation of vascular tone in renal, cerebral, coronary, and skeletal muscle arterioles, and in the pulmonary circulation. CYP450 enzymes form the 3rd pathway of arachidonic acid (AA) metabolize AA. CYP450-derived arachidonic acid metabolites play a role in the modulation of cerebrovascular pathology and physiology. CYP4F2 and CYP4A11 are members of the family of CYP450 enzymes, and mainly act as enzymes that is involved not only in the metabolism of leukotriene B4 (LTB4), but also 20-HETE. It has been reported that cerebral infarction is associated with the polymorphism of rs2108622.However the association results of these candidate genes in different regions and for different ethnic population have not been effectively reapeated and confirmed. In view of northern Chinese population with higher incidence of IS, it is necessary to carry out an association study of candidated susceptible genes aimed at northern China region Han population IS.Atherosclerosis is an important pathophysiological basis of IS, and inflammatory reaction process is of great significance in atherosclerosis formation, Leukotriene signaling has been implicated in early lipid retention and foam cell accumulation, as well as in the development of intimal hyperplasia and advanced atherosclerotic lesions. Furthermore, the association of leukotrienes with degradation of extracellular matrix has suggested a role in atherosclerotic plaque rupture. Studies in animals and in vitro suggest that both LTB4 and cysteinyl leukotrienes participate in the development of atherosclerotic lesions. LTC4 synthase lead LTA4 to LTC4, D4 and E4 (collectively referred to as the cysteinyl-LTs). so our study selected inflammation-related LTC4 synthase gene. By introducing candidate genes case-control association analysis, we mesured LTC4 synthase gene allele frequencies between IS group. So we can provide IS molecular epidemiology data for comprehensively understanding IS potential genetic mechanisms and more early IS molecular biology diagnosis indicators.Materials and methodsA case-control design was introduced. The subjects of IS group were consecutively recruited from northern China region patients with a total of 302 cases male 193,female 109, aged 40-80 years old, Han nationality, no consanguinity with each other. The controls matched by age, sex, and ethnic orign were recruited from the same patients geographic region, with a total of 350 cases, male 212, female 138. Accordting to the different causes the patients were divided into two subgroups:the large vessels group (thrombotic cerebral infarction group) and the small vessels group(lacunar infarction group). CYP4F2 gene rs2108622, rs3093100, rs3093105, rs3093135; CYP4A11 gene rs9333025 and LTC4S gene rs73002 SNPs were genotyped by polymerase chain reaction and restriction fragment length polymorphism(PCR-RFLP) analysis.CYP4F2 gene rs1558139 and LTC4S gene rs331446829 SNPs were genotyped by means of Matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF) primer extension reaction. Genotyping results were confirmed by squencing method. SPSS 13.0 statistical software was used for data processing. Continuous variables were expressed as mean±SE and were assessed by One-Way ANOVA. Genotype and allele frequencies were calculated for control group and each of the patient groups. Univariate comparisons of allele and genotype distributions were done usingχ2 test. Theχ2 goodness of fit test was used to test for deviation of genotype distribution from Hardy-Weinberg equilibrium. Conditional Logistic Regression adjusted for IS traditional risk factors including age, blood pressure, blood sugar, blood lipids and smoking. The influence of CYP4F2,CYP4A11 and LTC4S gene polymorphisms on IS was indicated by odds ratio(OR) and 95% confidenc(CI) with P＜0.05 as significant criteria. Haplotype-based analysis was infered by using Shesis online-software. The synergistic action of CYP4F2 gene,CYP4Allgene and LTC4S gene for IS was analysed by UNPHASED 3.0.7 version software.Results1. The genotype frequencies of all SNPs conformed to the expectations of Hardy-Weinberg equilibrium(P＞0.05). It was suggested that the selected samples could represent the population and were suitable for genetic analysis.2. CYP4F2 gene rs2108622 SNP frequencies distributions among the patients and the controls:rs2108622 G/G genotyp frequencies of the male IS group were higher than the male control group (OR=2.53; 95%CI:1.15-5.56; P=0.018), and after logistic regression the differece was still significant OR=1.78; 95%CI:1.120～2.854; P=0.015 (GG vs AA+GA)), (OR=3.14; 95%CI 1.283-7.71; P=0.012(GG+GA vs AA)). G allele frequencies of the male IS group were higher than the male control group (OR=1.48; 95%CI:1.09-2.02; P=0.013).There were no significant differences with regard to G/G genotyp frequencies between the IS patients and the control and female.3. CYP4F2 gene rs3093100,rs3093105,rs3093135 and rs1558139 SNPs frequencies distributions among the patients and the controls:There were no significant differences with regard to rs3093100 C/C genotyp frequencies between the IS patients and the control,males and females (P＞0.05). There were no significant differences with regard to rs3093105 T/T genotyp frequencies between the IS patients and the control,males and females (P＞0.05). There were no significant differences with regard to rs3093135 T/T genotyp frequencies between the IS patients and the control,males and females (P＞0.05). There were no significant differences with regard to rs1558139 G/G genotyp frequencies between the IS patients and the control,males and females (P＞0.05).4. CYP4F2 gene haplotype frequencies among the patients and the controls:5 haplotypes were identified among the patients and the controls, GGGT haplotype frequencies of the IS group were higher than the control group (OR= 1.339; 95%CI: 1.051-1.706; P=0.017);6 haplotypes were identified among the male patients and the male controls, the GGGT haplotype frequencies of the male cases were higher than the male control group (OR= 1.545; 95%CI:1.144-2.087; P=0.004); 8 haplotypes were identified among the female patients and the female, significant differences of all the haplotypes were not observed in the female IS group and the female control group (P＜0.05).5. CYP4A11 gene rs9333025 SNP frequencies distributions among the patients and the controls:rs9333025G/G genotyp frequencies of IS group were higher than the control group(P=0.02, OR=1.698,95%CI:1.207-2.389), and after logistic regression the differece was still significant(P=0.01,OR=1.721,95%CI:1.141-2.594)rs9333025 G allele frequencies of the IS group were higher than the control group (OR=1.661; 95%CI:1.22-2.24; P=0.001)6. LTC4S gene rs730012 SNP frequencies distributions among the patients and the controls:rs730012 C/C genotyp frequencies of the control group were lower than the IS group (OR=3.41; 95%CI:1.257-9.245;P=0.011), and after logistic regression the differece was still significant (OR=0.892; 95%CI:0.797-0.998; P=0.047)7. LTC4S gene rs331446827 SNP frequencies distributions among the patients and the controls:There were no significant differences with regard to rs331446827 A/A genotyp frequencies between the IS patients and the control. Conclusions1,CYP4F2 gene rs2108622 G/G genotype might be the independent risk factors of northern China region han population ischemic strke, and its risk mainly came from G allele.2,There were no association between the polymorphisms of rs3093100, rs3093105,rs3093135 and rsl558139 and northern China region han population ischemic strke.3,CYP4F2 gene GCGA haplotype might be at-risk haplotype of IS4,CYP4A11 gene rs9333025 G/G genotype might be associated with IS.G allele might be risk allele5,LTC4S gene rs730012 C/C genotype might be protective.6,There was no association between the SNP of rs331446827 and IS.