Are Genetic Variants Associated with the Location of Cerebral Arterial Lesions in Stroke Patients?

Rare RNF213 variants is related to early-onset intracranial atherosclerosis: A Chinese community-based study

BACKGROUND

The relationship between rare variants in Ring finger protein 213 (RNF213) and intracranial atherosclerosis (ICAS) remained unelucidated. Using whole-exome sequencing (WES) and high-resolution magnetic resonance imaging (HR-MRI), this study aimed at investigating the association between rare RNF213 variants and ICAS within a Chinese community-dwelling population.

METHODS

The present study included 821 participants from Shunyi cohort. Genetic data of rare RNF213 variants were acquired by WES and were categorized by functional domains. Intracranial and extracranial atherosclerosis were assessed by brain HR-MRI and carotid ultrasound, respectively. Logistic regression and generalized linear regression were applied to evaluate the effects of rare RNF213 variants on atherosclerosis. Stratification by age were conducted with 50 years old set as the cutoff value.

RESULTS

Ninety-five participants were identified as carriers of rare RNF213 variants. Carotid plaques were observed in 367 (44.7 %) participants, while ICAS was identified in 306 (37.3 %). Rare variants of RNF213 was not associated with ECAS. Employing HR-MRI, both the presence of rare variants (β = 0.150, P = 0.025) and numerical count of variants (β = 0.182, P = 0.003) were significantly correlated with ICAS within the group of age ≤50 years. Both variant existence (β = 0.154, P = 0.014) and variant count (β = 0.188, P = 0.003) were significantly associated with plaques in middle cerebral arteries within younger subgroup, rather than basilar arteries. Furthermore, a significant association was observed between variants that located outside the N-arm domain and ICAS in the younger subgroup (OR = 2.522, P = 0.030). Statistical results remained robust after adjusted for age, gender, and cardiovascular risk factors.

CONCLUSIONS

Rare variants of RNF213 is associated with age-related ICAS in general Chinese population, highlighting the potential role of RNF213 as a genetic contributor to early-onset ICAS.

Clinical characteristics and intracranial arterial lesions of non-young adult ischemic stroke patients with RNF213 p.R4810K variant

BACKGROUND

Although RNF213 p.R4810K, a genetic susceptibility variant for moyamoya disease (MMD), is associated with intracranial artery stenosis/occlusion (ICASO), the impact of this variant on ischemic stroke patients in non-young adults is unclear. We aimed to determine the characteristics of non-young adult stroke patients with RNF213 p.R4810K.

METHODS

We retrospectively identified acute ischemic stroke patients ≥50 years who were admitted to our hospital and underwent intracranial vascular imaging. We reviewed the patients with RNF213 p.R4810K and compared stroke characteristics and the frequency and location of ICASO between patients with and without the variant.

RESULTS

Among 341 patients, RNF213 p.R4810K was identified in 7 patients (2.1%). Five of the 7 patients with the variant (71%) had multiple ICASO without any finding of MMD and remaining 2 patients had no ICASO. The presumed etiologies of ICASO were atherosclerosis in 3 cases, vasculitis in 1, and undetermined vasculopathy in 1. ICASO in the anterior circulation was more common in patients with the variant than in those without (71% vs. 25%). The internal carotid artery, the M1 segment of the middle cerebral artery, the A1 segment of the anterior cerebral artery, and the P1 segment of the posterior cerebral artery, which were the most frequently affected arteries in MMD, were more often affected in the variant group.

CONCLUSIONS

Non-young adult stroke patients with RNF213 p.R4810K are more likely to have ICASO in arterial segments commonly affected in MMD. The etiology of their ICASO exhibited diverse mechanisms, possibly depending on vascular risk and other environmental factors.

MMP9 SNP and MMP SNP-SNP interactions increase the risk for ischemic stroke in the Han Hakka population

OBJECTIVES

To investigate the association of eight variants of four matrix metalloproteinase (MMP) genes with ischemic stroke (IS) and whether interactions among these single nucleotide polymorphisms (SNPs) increases the risk of IS.

METHODS

Among 547 patients with ischemic stroke and 350 controls, matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to examine eight variants arising from four different genes, including MMP-1 (rs1799750), MMP-2 (rs243865, rs2285053, rs2241145), MMP-9 (rs17576), and MMP-12 (rs660599, rs2276109, and rs652438). Gene-gene interactions were employed using generalized multifactor dimensionality reduction (GMDR) methods.

RESULTS

The frequency of rs17576 was significantly higher in IS patients than in controls (p = .033). Logistic regression analysis revealed the AG and GG genotypes of rs17576 to be associated with a higher risk for IS, with the odds ratio and 95% confidence interval being 2.490 (1.251-4.959) and 2.494 (1.274-4.886), respectively. GMDR analysis showed a significant SNP-SNP interaction between rs17576 and rs660599 (the testing balanced accuracy was 53.70% and cross-validation consistency was 8/10, p = .0107). Logistic regression analysis showed the interaction between rs17576 and rs660599 to be an independent risk factor for IS with an odds ratio of 1.568 and a 95% confidence interval of 1.152-2.135.

CONCLUSION

An MMP-9 rs17576 polymorphism is associated with increased IS risk in the Han Hakka population and interaction between MMP-9 rs17576 and MMP-12 rs660599 is associated with increased IS risk as well.