HTRA1 Variants and the Interaction with Smoking Confer the Genetic Susceptibility to Ischemic Stroke

Association Between HTRA1, GAS6 and IFNGR2 Gene Polymorphisms and Stroke Susceptibility in the Chinese Han Population

Background

Stroke has a high disability rate, and 30% of stroke cases have an unknown cause. Accurate diagnosis and treatment of stroke requires consideration of several rare heritable and non-heritable factors.

Objective

This study aimed to evaluate the impacts of three genetic polymorphisms (rs369149111 in HTRA1, rs1803628 in GAS6 and rs9808753 in IFNGR2) on stroke susceptibility among the Chinese Han population.

Methods

Three single nucleotide polymorphisms (SNPs) from 623 stroke cases and 572 healthy controls were genotyped by the Agena MassARRAY platform. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression analysis to evaluate the associations of three SNPs with stroke susceptibility. Additionally, SNP-SNP interactions were analyzed by multifactor dimensionality reduction (MDR).

Results

As demonstrated by the overall analysis, rs9808753 in IFNGR2 (allele: OR = 1.25, 95% CI = 1.06-1.47, p = 0.007; homozygous: OR = 1.59, 95% CI = 1.14-2.23, p = 0.007; dominant: OR = 1.31, 95% CI = 1.02-1.67, p = 0.032; recessive: OR = 1.42, 95% CI = 1.05-1.91, p = 0.022; additive: OR = 1.26, 95% CI = 1.07-1.48, p = 0.007) was associated with an increased susceptibility to stroke. Besides, stratification analysis suggested that rs9808753 was associated with an increased risk of stroke in subgroup aged ≤ 64 years, males and drinkers (p < 0.05). And rs1803628 in GAS6 was significantly associated with an increased susceptibility to stroke in non-smokers (p < 0.05).

Conclusion

A risk-increasing effect of IFNGR2 rs980875 on stroke was detected in this study, which further broadens the understanding of the relationship between genetic polymorphisms and stroke susceptibility.

A potential relationship between MMP-9 rs2250889 and ischemic stroke susceptibility

Purpose

Ischemic stroke (IS), a serious cerebrovascular disease, greatly affects people's health and life. Genetic factors are indispensable for the occurrence of IS. As a biomarker for IS, the MMP-9 gene is widely involved in the pathophysiological process of IS. This study attempts to find out the relationship between MMP-9 polymorphisms and IS susceptibility.

Methods

A total of 700 IS patients and 700 healthy controls were recruited. The single nucleotide polymorphism (SNP) markers of the MMP-9 gene were genotyped by the MassARRAY analyzer. Multifactor dimensionality reduction (MDR) was applied to generate SNP-SNP interaction. Furthermore, the relationship between genetic variations (allele and genotype) of the MMP-9 gene and IS susceptibility was analyzed by calculating odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Our results demonstrated that rs2250889 could significantly increase the susceptibility to IS in the codominant, dominant, overdominant, and log-additive models (p < 0.05). Further stratification analysis showed that compared with the control group, rs2250889 was associated with IS risk in different case groups (age, female, smoking, and non-drinking) (p < 0.05). Based on MDR analysis, rs2250889 was the best model for predicting IS risk (cross-validation consistency: 10/10, OR = 1.56 (1.26-1.94), p < 0.001).

Conclusion

Our study preliminarily confirmed that SNP rs2250889 was significantly associated with susceptibility to IS.

HTRA1 methylation in peripheral blood as a potential marker for the preclinical detection of stroke: a case-control study and a prospective nested case-control study

BACKGROUND

Stroke is the leading cause of mortality in China. DNA methylation has essential roles in multiple diseases, but its association with stroke was barely studied. We hereby explored the association between blood-based HTRA serine protease 1 (HTRA1) methylation and the risk of stroke.

RESULTS

The association was discovered in a hospital-based case-control study (cases/controls = 190:190) and further validated in a prospective nested case-control study including 139 cases who developed stroke within 2 years after recruitment and 144 matched stroke-free controls. We observed stroke-related altered HTRA1 methylation and expression in both case-control study and prospective study. This blood-based HTRA1 methylation was associated with stroke independently from the known risk factors and mostly affected the older population. The prospective results further showed that the altered HTRA1 methylation was detectable 2 years before the clinical determination of stroke and became more robust with increased discriminatory power for stroke along with time when combined with other known stroke-related variables [onset time ≤ 1 year: area under the curve (AUC) = 0.76].

CONCLUSIONS

In our study, altered HTRA1 methylation was associated with stroke at clinical and preclinical stages and thus may provide a potential biomarker in the blood for the risk evaluation and preclinical detection of stroke.

Impact of MMP2 rs243849 and rs14070 genetic polymorphisms on the ischemic stroke susceptibility in Chinese Shaanxi population

Background

Ischemic stroke (IS) is a complex neurological disease affected by genetics and environment. Matrix metalloproteinase-2 (MMP2) is involved in extracellular matrix (ECM) degradation, inflammation and angiogenesis to regulate the development and recovery of IS.

Purposes

The aim of this study was to explore the association of rs1053605, rs243849 and rs14070 in MMP2 with the risk of IS in Chinese Shaanxi population.

Methods

In this study, 677 IS patients and 681 normal controls were recruited. Rs1053605, rs243849 and rs14070 in MMP2 were genotyped. Logistic regression analysis was applied to evaluate the association of rs1053605, rs243849 and rs14070 in MMP2 with IS susceptibility and the association of environmental factors with MMP2 genetic susceptibility to IS.

Results

The results of the overall analysis demonstrated that rs14070 in MMP2 significantly reduced the risk of IS in Chinese Shaanxi population (OR = 0.767, 95% CI = 0.619–0.952, P = 0.016). Subgroup analysis illustrated that rs243849 in MMP2 evidently increased the risk of IS among drinkers, while rs14070 in MMP2 apparently reduced IS susceptibility among females, participants with aged >55, smokers and drinkers.

Conclusions

Collectively, rs243849 and rs14070 in MMP2 were significantly associated with the risk of IS in Chinese Shaanxi population, and the effect of MMP2 to IS may be associated with its genetic susceptibility.