Polymorphism in Genes Encoding Adaptor Proteins ST13 and STIP1 and the Risk of Ischemic Stroke: a Pilot Study

Adaptor proteins stress induced phosphoprotein 1 (STIP1) and ST13 Hsp70 interacting protein (ST13) may play a crucial role in the pathophysiology of ischemic stroke through controlling protein folding, neuronal survival, and regulation of HSP70/HSP90. The present pilot study investigated whether tagSNPs in genes encoding ST13 (rs138335, rs138344, rs7290793, and rs138344) and STIP1 (rs4980524) are associated with ischemic stroke. DNA samples from 721 ischemic stroke patients and 471 healthy controls were genotyped using the MassArray-4. Our research revealed a relationship between rs138344 ST13 and the risk of ischemic stroke, which was seen only in females (risk allele G; OR=1.34, 95%CI=1.07-1.69; p=0.01). The haplotype rs138335G-rs138344C-rs7290793C ST13 was linked with lower risk of ischemic stroke in females: OR=0.42; 95%CI=0.26-0.68; p=0.0005. Thus, ST13 represents a novel genetic marker for ischemic stroke.

Polymorphism of SERF2, the gene encoding a heat-resistant obscure (Hero) protein with chaperone activity, is a novel link in ischemic stroke

Background

Ischemic stroke (IS) is one of the most serious cardiovascular events associated with high risk of death or disability. The growing body of evidence highlights molecular chaperones as especially important players in the pathogenesis of the disease. Since six small proteins called "Hero" have been recently identified as a novel class of chaperones we aimed to evaluate whether SNP rs4644832 in SERF2 gene encoding the member of Hero-proteins, is associated with the risk of IS.

Methods

A total of 1929 unrelated Russians (861 patients with IS and 1068 healthy individuals) from Central Russia were recruited into the study. Genotyping was done using a probe-based PCR approach. Statistical analysis was carried out in the whole group and stratified by age, gender and smoking status.

Results

Analysis of the link between rs4644832 SERF2 and IS showed that G allele is the risk factor of IS only in females (OR=1.29, 95%CI 1.02-1.64, Padj=0.035). In addition, the analysis of associations of rs4644832 SERF2 and IS depending on the smoking status revealed that this genetic variant is associated with an increased risk of IS exclusively in non-smoking individuals (OR=1.26, 95%CI 1.01-1.56, P = 0.041).

Discussion

Sex- and smoking interactions between rs4644832 polymorphism and IS may be related to the impact of tobacco components metabolism and sex hormones on SERF2 expression.

Conclusion

The present study reveals the novel genetic association between rs4644832 polymorphism and the risk of IS suggesting that SERF2, the part of the protein quality control system, contributes to the pathogenesis of the disease.

Association between HSPA8 Gene Variants and Ischemic Stroke: A Pilot Study Providing Additional Evidence for the Role of Heat Shock Proteins in Disease Pathogenesis

HSPA8 is involved in many stroke-associated cellular processes, playing a pivotal role in the protein quality control system. Here we report the results of the pilot study aimed at determining whether HSPA8 SNPs are linked to the risk of ischemic stroke (IS). DNA samples from 2139 Russians (888 IS patients and 1251 healthy controls) were genotyped for tagSNPs (rs1461496, rs10892958, and rs1136141) in the HSPA8 gene using probe-based PCR. SNP rs10892958 of HSPA8 was associated with an increased risk (risk allele G) of IS in smokers (OR = 1.37; 95% CI = 1.07-1.77; p = 0.01) and patients with low fruit and vegetable consumption (OR = 1.36; 95% CI = 1.14-1.63; p = 0.002). SNP rs1136141 of HSPA8 was also associated with an increased risk of IS (risk allele A) exclusively in smokers (OR = 1.68; 95% CI = 1.23-2.28; p = 0.0007) and in patients with a low fruit and vegetable intake (OR = 1.29; 95% CI = 1.05-1.60; p = 0.04). Sex-stratified analysis revealed an association of rs10892958 HSPA8 with an increased risk of IS in males (risk allele G; OR = 1.30; 95% CI = 1.05-1.61; p = 0.01). Thus, SNPs rs10892958 and rs1136141 in the HSPA8 gene represent novel genetic markers of IS.

[The combined effect of E298D polymorphism of the endothelial nitric oxide synthase gene and smoking on the risk of cerebral stroke]

Violations of the endothelium-dependent regulation of cerebral vessel tone are an important link in the pathogenesis of cerebrovascular disorders. The purpose of this study was to investigate the association of--86T>C and E298D polymorphisms of the endothelial nitric oxide synthase(NOS3) gene with the risk of ce-ebral stroke (CS) in Russian inhabitants of Central Russia, as well as to evaluate the trigger effect of smoking on the risk of CS in carriers of genotypes NOS3. Genotyping of-786T>C and E298D polymorphisms of the NOS3 gene was carried out through real time. CR and TaqMan allele discrimination assays. It was deter-ined that the genotype 298DD is associated with the risk of CS (OR =-1.71, 95% CII= 1.05-2.78, P= 0.03). Subsequent analysis showed that genotype 298 DD (OR = 3.75; 95% CII= 1.39-10.11; P= 0.01) is associatedw ith an increased risk of CS exclusively in smoking individuals. The combination ofg enotypes -786T/Cx298D/D was associated with the risk of CS. n smokers (OR = 7.71; 95% CI = 1.31-45.34; P = 0.02). In the present study, it was found that smoking is a significant modifying risk factor for cerebral stroke in the carriers of the 298DD and -786T/C. enotypes of endothelial nitric oxide synthase.

[GENDER-SPECIFIC DIFFERENCES OF ENDOTHELIAL NITRIC OXIDE SYNTHASE E298D POLYMORPHISM AND THE RISK OF STROKE]

Genetic factors can account for the differences in the frequency of stroke between men and women. Despite the scarcity of special clinico-genetic studies of stroke frequency in the two genders, analysis of association between DNA polymorphism and risk of stroke may reveal the influence of genetic factors on the sex-related predisposition to cerebrovascular diseases. The present work was aimed to study the relationship between frequent polymorphisms -786T > C of endothelial nitric oxide synthase (NOS3) gene E298D and the risk of stroke in men and women. 904 DNA samples were obtained from unrelated Russian residents of Central Russia including 480 stroke patients and 424 healthy volunteers. Genotyping was performed by PCR in real time with allele discrimination using TaqMan probes. The homoygous genotype of NOS3 gene E298D was found to be associated with an increased risk of stroke in men (OR 2.60; 95% CI 1.28-5.29, p = 0.01). Neither men nor women showed association of polymorphism -786T > C with the predisposition to stroke. The E298D genotype in men was associated with the enhanced risk of both ischemic (OR 2.38; 95% CI 1.14-4.96, p = 0.02) and hemorrhagic (OR 5,58; 95% CI 1.95-16.05, p = 0.003) stroke. Thus, NOS3 gene E298D polymorphism is a reliable predictor of predisposition to various pathogenetic variants of stroke only in men.