Genetic Analysis of Ring Finger Protein 213 ( RNF213 ) c.14576G>A in Intracranial Atherosclerosis of the Anterior and Posterior Circulations

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.

Prevalence of RNF213 rs112735431 Genetic Polymorphism in Non-Cardioembolic Ischemic Cerebrovascular Disease: A Cross-Sectional Study in Thai Patients

INTRODUCTION

Moyamoya disease (MMD) and non-MMD intracranial cerebral artery stenosis (ICAS) have been linked to the RNF213 rs112735431 gene in Korean and Japanese populations. This cross-sectional study investigates the prevalence of the RNF213 rs112735431 gene in non-cardioembolic ischemic stroke (NCIS) among Thai patients.

METHODS

A cross-sectional investigation was conducted on patients aged 18 years or older admitted to King Chulalongkorn Memorial Hospital between June 2015 and March 2016 with acute NCIS. ICAS and extracranial carotid artery stenosis (ECAS) were assessed through computer tomography angiography or magnetic resonance angiography. Blood samples were collected, and Sanger sequencing was performed.

RESULTS

Among 234 acute NCIS cases, 113 exhibited ICAS, 12 had ECAS, 20 had both, and 89 had neither. The RNF213 rs112735431 gene variant was detected in 2 patients, both heterozygous A/G. The frequency of the RNF213 rs112735431 variant was 0.9% (2/234; 95% CI: 0-2.1%) in acute NCIS patients and 1.8% (2/113; 95% CI: 0-4.2%) in ICAS. All individuals with the RNF213 variant were males with hypertension, diabetes mellitus, dyslipidemia, and ICAS, without a family history of ischemic stroke.

CONCLUSION

This study reveals that the RNF213 rs112735431 gene variant is uncommon among Thai NCIS patients, suggesting a discrepancy in the prevalence of this genetic variation between Thai and other Eastern Asian populations.

RNF213 Polymorphisms in Intracranial Artery Dissection

The ring finger protein 213 gene (RNF213) is involved in several vascular diseases, both intracranial and systemic ones. Some variants are common in the Asian population and are reported as a risk factor for moyamoya disease, intracranial stenosis and intracranial aneurysms. Among intracranial vascular diseases, both moyamoya disease and intracranial artery dissection are more prevalent in the Asian population. We performed a systematic review of the literature, aiming to assess the rate of RNF213 variants in patients with spontaneous intracranial dissections. Four papers were identified, providing data on 53 patients with intracranial artery dissection. The rate of RNF213 variants is 10/53 (18.9%) and it increases to 10/29 (34.5%), excluding patients with vertebral artery dissection. All patients had the RNF213 p.Arg4810Lys variant. RNF213 variants seems to be involved in intracranial dissections in Asian cohorts. The small number of patients, the inclusion of only patients of Asian descent and the small but non-negligible coexistence with moyamoya disease familiarity might be limiting factors, requiring further studies to confirm these preliminary findings and the embryological interpretation.

Common and distinct risk profiles of asymptomatic extra- and intracranial atherosclerosis in the Nagahama cohort

BACKGROUND AND PURPOSE

Atherosclerotic burden increases the risk of both extracranial internal carotid artery stenosis (ICS) and intracranial large artery disease (ICAD). However, the differences in risk profiles have not been thoroughly investigated.

METHODS

Participants were recruited from the Nagahama study cohort in Japan. Individuals over 60 years old who underwent 1.5-T head and neck magnetic resonance angiography (MRA) between July 2013 and February 2017 were included. ICAD was defined as WASID ≥ 50%, and ICS was defined as NSCET ≥ 30%. The prevalence and association of risk factors, including proatherogenic and proinflammatory factors, and the p.R4810K variant in the RNF213 gene, were investigated. Multivariable logistic regression analyses were performed.

RESULTS

A total of 3089 individuals participated in the study, with a mean age of 68.1 ± 5.3 years, and 36.0% were males. Among them, 52 (1.7%) had ICS, 119 (3.8%) had ICAD, and 15 (0.49%) had both conditions. Alopecia areata was an independent predictor for both ICS (Odds ratio [OR] 3.5; 95% CI 1.3-8.3) and ICAD (OR 2.1; 95% CI 1.0-3.9). Diabetes (OR 3.7; 95% CI 2.0-7.0) and older age (OR 2.4; 95% CI 1.2-4.5) were associated only with ICS, while the RNF213 variant was associated with only ICAD (OR 5.7; 95% CI 1.6-16.0). ICS and ICAD were also independently associated with each other.

CONCLUSIONS

In this MRA-based large scale study, alopecia areata, known as a systemic inflammatory disease, was shown to be a common risk factor for ICS and ICAD. While conventional atherosclerotic factors were associated with ICS, non-atherosclerotic factors appear to contribute to ICAD in Japan.

Moyamoya disease presenting with symptomatic ischemic stroke during new-generation tyrosine kinase inhibitor treatment: two illustrative cases

Tyrosine kinase inhibitors (TKIs) have been widely used to treat chronic myeloid leukemia. Nilotinib and ponatinib, which are second- and third-generation TKIs, have been reported to cause cerebrovascular arterial complications. Here, we present two cases of moyamoya disease presenting with symptomatic ischemic stroke during new-generation TKI treatment. We judged that new-generation TKI treatment was a factor in symptomatic ischemic stroke of unknown moyamoya disease in both cases. Noninvasive examinations using magnetic resonance imaging or carotid ultrasonography should be performed before and during new-generation TKI treatment in order to prevent symptomatic ischemic stroke.

The Vasodilatory Response to CGRP of the Anterior and Posterior Cerebral Circulation in Migraine

Introduction

Migraine aura can be associated with headache or it may occur without one, which suggests an independent mechanism for the aura and for migraine headache. The role of CGRP in migraine headache is well established, but the connection between CGRP and the aura is still lacking an explanation. Exogenous CGRP can induce CGRP headaches and migraine auras in patients with migraine. The results of our recent study suggest differences in the vascular response to CGRP stimulation between migraine without aura and migraine with aura. Therefore, we hypothesized that the magnitude of the posterior cerebral circulation response in migraine with aura is greater than in migraine without aura and that CGRP stimulation has different effects on the anterior and posterior circulation in migraine with aura and migraine without aura.

Methods

By using transcranial doppler, we studied the hemodynamic effects of CGRP intravenous infusion at a rate of 1.5 mcg/min in 20 min on the mean arterial velocity in the middle cerebral artery and in the posterior cerebral artery in twenty patients with migraine and in a control group of twenty healthy subjects. The same CGRP effects on cerebral hemodynamics were analyzed separately for the group of patients with migraine with aura and the group of patients with migraine without aura. Fifteen patients with migraine (75%) had migraine without aura and 5 patients (25%) had migraine with aura.

Results

We found that migraine has a significant impact on the vasodilatory response of the anterior (B = 4,249, SE = 1.023, r = 0.363, p < 0.001) and posterior cerebral circulation (B = 3.634, SE = 1.461, r = 0.227, p = 0.014). Migraine with aura was significantly associated with changes in the anterior (B = 2.558, SE = 0.880, r = 0.275, p = 0.005) and posterior cerebral circulation (B = 7.565, SE = 2,368, r = 0.359, p = 0.002), while migraine without aura was only significantly associated with changes in the anterior circulation. In addition, we established a significant impact of migraine with aura on VR PCA (B = 5.901, SE = 2,546, r = 0.291, p = 0.024).

Conclusion

We conclude that TVR in the posterior cerebral circulation might be enhanced in MA and that aura might be a consequence of TVR enhancement.

Relationship between PI3K-Akt pathway related gene polymorphisms and symptomatic intracranial atherosclerotic stenosis with hypertension in Chinese Han population

BACKGROUND

PI3K-Akt signaling was proved to be closely related to atherosclerosis, in which hypertension is an important risk factor for atherosclerosis. Studies have shown that genetic susceptibility is vital in the etiology of symptomatic intracranial atherosclerotic stenosis (sICAS), but few candidate genes were identified. This research explores latent connections between single nucleotide polymorphisms (SNPs) of PI3K-Akt related genes and sICAS with hypertension in Han Chinese subjects.

METHODS

Eight genes related to the PI3K-Akt pathway in 400 sICAS patients and 1007 healthy controls of Han nationality were sequenced, and further subgroup analysis based on hypertension was carried out. Chi-squared testing and multiple logistic regression in dominant, recessive, and additive models were used to evaluate the association between SNPs and risk of sICAS with hypertension. When linkage disequilibrium exists in different loci of the same gene, tagSNP represents the SNP in haplotype block.

RESULTS

There were 4 common variants of 1 candidate gene differently distributed between sICAS with or without hypertension. Among these four common variations, INSR rs3745551 was significantly related to the risk of sICAS with hypertension after multiple regression analysis, with the T allele being more prevalent in the sICAS with hypertension.

CONCLUSION

The variant of the INSR rs3745551 loci may be crucial in the pathogenesis of sICAS with hypertension in Chinese Han populations. Furthermore, the C allele at this locus may be a potentially harmful variant in sICAS with hypertension.

Ring finger protein 213 c.14576G>A mutation is not involved in internal carotid artery and middle cerebral artery dysplasia

The ring finger protein 213 (RNF213) susceptibility gene has been detected in more than 80% of Japanese and Korean patients with moyamoya disease (MMD), a bilateral internal carotid artery (ICA) occlusion. Furthermore, RNF213 has been detected in more than 20% of East Asians with atherosclerotic ICA stenosis. In this study, we evaluated the frequency of RNF213 mutations in congenital occlusive lesions of the ICA system. This case series was conducted jointly at four university hospitals. Patients with a family history of MMD, quasi-MMD, or related diseases were excluded. Ten patients were diagnosed with abnormal ICA or middle cerebral artery (MCA) angiogenesis. Patients with neurofibromatosis were excluded. Finally, nine patients with congenital vascular abnormalities were selected; of these, five had ICA deficiency and four had twig-like MCA. The RNF213 c.14576G > A mutation was absent in all patients. Therefore, the RNF213 c.14576G > A mutation may not be associated with ICA and MCA congenital dysplasia—rare vascular anomalies making it difficult to study a large number of cases. However, an accumulation of cases is required for accurate determination. The results of this study may help differentiate congenital vascular diseases from MMD.

RNF213 c.14576G>A Is Associated with Intracranial Internal Carotid Artery Saccular Aneurysms

A mutation in RNF213 (c.14576G>A), a gene associated with moyamoya disease (>80%), plays a role in terminal internal carotid artery (ICA) stenosis (>15%) (ICS). Studies on RNF213 and cerebral aneurysms (AN), which did not focus on the site of origin or morphology, could not elucidate the relationship between the two. However, a report suggested a relationship between RNF213 and AN in French-Canadians. Here, we investigated the relationship between ICA saccular aneurysm (ICA-AN) and RNF213. We analyzed RNF213 expression in subjects with ICA-AN and atherosclerotic ICS. Cases with a family history of moyamoya disease were excluded. AN smaller than 4 mm were confirmed as AN only by surgical or angiographic findings. RNF213 was detected in 12.2% of patients with ICA-AN and 13.6% of patients with ICS; patients with ICA-AN and ICS had a similar risk of RNF213 mutation expression (odds ratio, 0.884; 95% confidence interval, 0.199-3.91; p = 0.871). The relationship between ICA-AN and RNF213 (c.14576G>A) was not correlated with the location of the ICA and bifurcation, presence of rupture, or multiplicity. When the etiology and location of AN were more restricted, the incidence of RNF213 mutations in ICA-AN was higher than that reported in previous studies. Our results suggest that strict maternal vessel selection and pathological selection of AN morphology may reveal an association between genetic mutations and ICA-AN development. The results of this study may form a basis for further research on systemic vascular diseases, in which the RNF213 (c.14576G>A) mutation has been implicated.

Genetic Risk Factors of Intracranial Atherosclerosis

PURPOSE OF REVIEW

Intracranial atherosclerosis (ICAS) is the most common cause of stroke throughout the world. It also increases the risk of recurrent stroke and dementia. As a complex and multifactorial disease, ICAS is influenced by multiple genetic, biological, and environmental factors. This review summarizes the candidate gene and genome-wide studies aimed at discovering genetic risk factors of ICAS.

RECENT FINDINGS

Numerous studies have focused on the association between single-nucleotide polymorphisms (SNPs) of atherosclerosis-related genes and the risk of ICAS. Variants in adiponectin Q (ADIPOQ), ring finger protein 213 (RNF213), apolipoprotein E (APOE), phosphodiesterase 4D (PDE4D), methylenetetrahydrofolate reductase (MTHFR), lipoprotein lipase (LPL), α-adducin (ADD1) genes, angiotensin-converting enzyme (ACE), and other genes related to renin-angiotensin-aldosterone system have been associated with ICAS. We review the available evidences on the candidate genes and SNPs associated with genetic susceptibility to ICAS, and point out future developments of this field. Genetic discoveries could have clinical implications for intracranial atherosclerotic disease.

Hemorrhagic Onset Intracranial Artery Dissection of Middle Cerebral Artery Followed by Progressive Arterial Stenosis with Genetic Variant RNF213 p.Arg4810Lys (rs112735431)

BACKGROUND

Intracranial arterial dissection (IAD) is known to exhibit various patterns of arterial imaging features such as stenosis and dilation; however, the genetic background of IAD has not been elucidated so far. RNF213 was recently identified as a susceptibility gene for moyamoya disease (MMD) and intracranial artery stenosis (ICAS). More recently, RNF213 p.Arg4810Lys also has been shown to be associated with various systemic vascular diseases. RNF213 p.Arg4810Lys is beginning to attract attention as a genetic factor that causes systemic vascular disease.

CASE DESCRIPTION

Herein, we report a rare case of de novo progression of the intracranial vascular lesion with the RNF213 p.Arg4810Lys variant, which first presented IAD of the middle cerebral artery (MCA) with subarachnoid hemorrhage, second progressed into ICAS, and finally evolved into MMD-like angiogenesis over 6 years.

CONCLUSIONS

This case suggests that IAD of the MCA could be associated with RNF213 p.Arg4810Lys variant. This genetic variant could also have a key role in the overlap among the different disease states. A large-scale genetic analysis study of the IADs of the anterior circulation is needed. To qualify the significance of RNF213 p.Arg4810Lys variant as a stroke risk allele, accumulation of various cases of cerebrovascular lesions would be essential.

Association of Genetic Variants With Moyamoya Disease in 13 000 Individuals: A Meta-Analysis

Background and Purpose- A growing body of evidence indicates genetic components play critical roles in moyamoya disease (MMD). Firm conclusions from studies of this disease have been stymied by small sample sizes and a lack of replicative results. This meta-analysis was conducted to determine whether these genetic polymorphisms are associated with MMD. Methods- PubMed, Google Scholar, Embase, Wanfang, Web of Science, and China National Knowledge Infrastructure databases were used to identify potentially relevant studies published until January 2020. The Review Manager 5.2 and Stata 15.0 software programs were used to perform the statistical analysis. Heterogeneity was assessed using the Cochran Q test and quantified using the I² test. Results- Four thousand seven hundred eleven MMD cases and 8704 controls in 24 studies were included, evaluating 7 polymorphisms in 6 genes. The fixed-effect odds ratios (95% CI) in allelic model of MMP-2 rs243865 were 0.60 (0.41-0.88) (P=0.008). In the country-based subgroup analysis, the fixed-effect odds ratios (95% CI) of RNF213 rs112735431 in allelic model were China, 39.74 (26.63-59.31), Japan, 74.65 (42.79-130.24) and Korea, 50.04 (28.83-86.88; all P<0.00001). In the sensitivity analysis, the fixed-effect odds ratios (95% CI) of allelic and dominant models were the RNF213 rs148731719 variant, 2.17 (1.36-3.48; P=0.001), 2.20 (1.35-3.61; P=0.002), the TIMP-2 rs8179090 variant, 0.33 (0.25-0.43; P<0.00001), 0.88 (0.65-1.21; P=0.440) and the MMP-3 rs3025058 variant, 0.61 (0.47-0.79; P=0.0002), 0.55 (0.41-0.75; P=0.0001), respectively. Conclusions- RNF213 rs112735431 and rs148731719 were positively, and TIMP-2 rs8179090, MMP-2 rs243865, and MMP-3 rs3025058 were inversely associated with MMD using multiple pathophysiologic pathways. Studies in larger population should be conducted to clarify whether and how these variants are associated with MMD.

Distribution of Intracranial Major Artery Stenosis/Occlusion According to RNF213 Polymorphisms

Intracranial major artery stenosis/occlusion (ICASO) is the major cause of ischemic stroke. Recent studies have suggested that variants of RNF213, a susceptibility gene for moyamoya disease (MMD), are also related to non-MMD ICASO. Regarding the predominant involvement of steno-occlusion on anterior circulation in MMD, we hypothesized that the ICASO distribution pattern (anterior/posterior) in non-MMD may differ according to RNF213 variants. This study analyzed 1024 consecutive Korean subjects without MMD who underwent computed tomography angiography (CTA) or magnetic resonance angiography (MRA). We evaluated four single nucleotide polymorphisms (SNPs) in the exon region of RNF213: 4448G > A (rs148731719), 4810G > A (rs112735431), 4863G > A (rs760732823), and 4950G > A (rs371441113). Associations between RNF213 variants and anterior/posterior ICASO were examined using multivariate logistic regression analysis. Anterior ICASO was present in 23.0% of study subjects, and posterior ICASO was present in 8.2%. The GA genotype of RNF213 4810G > A (adjusted odds ratio (AOR) [95% confidence interval (CI)], 2.39 [1.14-4.87] compared to GG; p = 0.018) and GA genotype of RNF213 4950G > A (AOR [95% CI], 1.71 [1.11-2.63] compared to GG; p = 0.015) were more frequent in subjects with anterior ICASO. The genotype frequency of RNF213 4863G > A differed significantly according to the presence of posterior ICASO. Further investigations of the functional and biological roles of RNF213 will improve our understanding of the pathomechanisms of ICASO and cerebrovascular disease.

Prevalence of RNF213 variants in symptomatic intracranial arterial stenosis/occlusion in China

The ring finger protein 213 gene (RNF213) rs112735431 was significantly associated with intracranial artery stenosis/occlusion disease (ICASO) in Japan and Korea and to a lesser degree in China. We conducted a case-control study to examine the prevalence and correlates of the RNF213 rare variants in Chinese patients with symptomatic ICASO. A total of 503 cases including 390 ischemic stroke patients (ICASO-IS), 113 intracranial hemorrhage patients (ICASO-ICH) and 227 control subjects were recruited. The snapshot technique was used for RNF213 rare variants analysis, including rs112735431, rs148731719, rs37144111 and rs138130613. Moreover, a meta-analysis was performed to explore the relationship between RNF213 variants and ICASO in Asian. In our case-control study, we found that the rs138130613 variant was significantly associated with ICASO-IS (OR = 9.92, 95% CI 1.24-79.19, p = 0.03). The mean age of first ischemic stroke onset of variant carriers was earlier than the noncarriers (51.3 ± 18.0 versus 66.0 ± 12.9 years old, p = 0.02), but the conventional atherosclerotic risk factors and the characteristics of artery stenosis did not differ between them. In addition, the meta-analysis showed significant association between the rs112735431 polymorphism and the ICASO or ICASO-IS, and this variant was found more often in women and young-onset patients in Asia. This study suggests that the RNF213 rs112735431 and rs138130613 are genetic risk variants for ischemic stroke with intracranial artery stenosis/occlusion in China and rs112735431 is also associated with the high risk of ICASO in Asia. Further large-scale investigation of the RNF213 gene will provide new insights into pathogenetic mechanisms of symptomatic ICASO.

Developing Novel Therapeutic Strategies Against Ring Finger Protein 213 Vasculopathy: Is It an Achievable Goal?

See Article Choi et al.

Rare RNF213 variants and the risk of intracranial artery stenosis/occlusion disease in Chinese population: a case-control study

BACKGROUND

RNF213 rare variant-p.R4810K (rs112735431) was significantly associated with intracranial artery stenosis/occlusion disease (ICASO) in Japan and Korea and to a lesser degree in China. Considering the allelic heterogeneity, we performed target exome sequencing of RNF213 with the aim to identify the rare variants spectrum and their association with ICASO in a Chinese population and further to explore whether the rare variants carrier patients present specific clinical phenotype.

METHODS

Target exome sequencing of RNF213 was performed in 250 ICASO patients using FastTarget sequencing technology. Various filtering process were used to select the candidate variants. Control individuals were obtain from 1000 Genome Project (208 Chinese samples) and GeneSky in-house database (1007 samples). Gene-based association analyses were conducted to identify the association between RNF213 rare variants and ICASO. The clinical characteristics of rare variant carriers and non-carriers were compared using Chi-squared test or Fisher's exact test.

RESULTS

After filtration, 18 rare variants were identified in 39 patients. Gene-based association test showed that rare variants of RNF213 were significantly associated with ICASO (Minor allele frequency < 0.05, WSS p = 4.88 × 10^- 10; SKAT p = 9.68 × 10^- 6; SKAT-O p = 3.42 × 10^- 9). There were no significant clinical characteristic differences other than the diagnosis age which was older in the carriers than the non-carriers (60.5 ± 6.2 vs 57.3 ± 8.9 years old, p = 0.028).

CONCLUSION

Rare variants of RNF213 are associated with ICASO in Chinese. However, there are limited genetic diagnosis values of the gene due to no specific phenotypic presentation in the carriers and non carrier patients.

RNF213 Variant Diversity Predisposes Distinct Populations to Dissimilar Cerebrovascular Diseases

In recent years, the ring finger protein 213 gene (RNF213) has gradually attracted attention, mainly because it has been found that RNF213 c.14429 G>A is associated with moyamoya disease (MMD) in East Asian populations. Recent studies have revealed that RFN213 is not only associated with MMD but is also connected with intracranial major artery stenosis/occlusion (ICASO) and intracranial aneurysm (IA). However, only the relationship between RNF213 c.14429 G>A and ICASO has been confirmed, and whether RNF213 has other mutations related to ICASO remains unclear. RNF213 and IA are currently only confirmed to be correlated in French-Canadian Population and no correlation has been found in the Japanese population. This review summarizes the advances in the associations between RNF213 and different cerebrovascular diseases and highlights that variant diversity of RNF213 may predispose distinct populations to dissimilar cerebrovascular diseases.

Rare variants of RNF213 and moyamoya/non-moyamoya intracranial artery stenosis/occlusion disease risk: a meta-analysis and systematic review

Background

The p.R4810K and other rare variants of ring finger protein 213 gene (RNF213) were illustrated as susceptibility variants for moyamoya (MMD) and non-moyamoya intracranial artery stenosis/occlusion disease (ICASO) recently. However, the effect sizes of p.R4810K were in great discrepancy even in studies of the same ethnic population and firm conclusions of other rare variants have been elusive given the small sample sizes and lack of replication. Thus, we performed this study to quantitatively evaluate whether or to what extent the rare variants of RNF213 contribute to MMD and ICASO in different populations.

Methods

A systematic search of PubMed, EMBASE, ISI web of science, CNKI, and WANFANG DATA was conducted up to 5 September 2017. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random- or fixed-effect models based on the between-study heterogeneity. The subgroup analyses were performed by the ethnicity and family history. Sensitivity and publication bias analysis were performed to test the robustness of associations. All the statistical analyses were conduct using STATA 12.0.

Results

Twenty studies including 2353 MMD cases and 5488 controls and 11 studies including 1778 ICASO cases and 3140 controls were included in this study. Pooled ORs indicated that RNF213 p.R4810K significantly increased MMD and ICASO risk in East Asians with great effect sizes of discrepancy (dominant model: odds ratios 184.04, 109.77, and 31.53 and 10.07, 28.52, and 5.59 for MMD and ICASO, respectively, in Japan, Korea, and China). It significantly increased familial MMD risk in Japan, Korea, and China with 5 ~ 36 times larger effect sizes than that for sporadic ones in each country (dominant model ORs 1802.44, 512.42, 1109.02 and 134.35, 99.82, and 30.52, respectively, for familial and sporadic cases). The effect sizes of RNF213 p.R4810K to sporadic MMD were 3 ~ 4 times larger in Japan and Korea than those in China. RNF213 p.R4810K also increased the ICASO risk in Japan and Korea with 2 ~ 4 times larger effect sizes than that in China (dominant model ORs 10.71, 28.52, and 5.59, respectively). Another two rare variants- p.E4950D and p.A5021V significantly increased MMD risk in Chinese population (dominant model ORs 9.06 and 5.01, respectively). Various other rare variants in RNF213 were identified in Japanese, Chinese, European, and Hispanic American populations without association evidence available yet.

Conclusions

This meta-analysis shows the critical roles of RNF213 p.R4810K in MMD especially familial MMD and ICASO in Japan, Korea, and China. Except for RNF213 p.R4810K, MMD seems to have more complex determiners in China. Distinct genetic background exists and other environmental or genetic factor(s) may contribute to MMD. Studies focused on delineating the ethnicity-specific factors and pathological role of RNF213 variants in MMD and ICASO are needed.

Electronic supplementary material

The online version of this article (10.1186/s12199-017-0680-1) contains supplementary material, which is available to authorized users.