Ethnic variation and the relevance of homozygous RNF 213 p.R4810.K variant in the phenotype of Indian Moya moya disease

RNF213 in moyamoya disease: Genotype-phenotype association and the underlying mechanism

ABSTRACT

Moyamoya disease (MMD) is a cerebrovascular disorder characterized by a steno-occlusive internal carotid artery and compensatory vascular network formation. Although the precise pathogenic mechanism remains elusive, genetic association studies have identified RNF213 as the principal susceptibility gene for MMD, with the single nucleotide polymorphism p.R4810K recognized as the founder variant predominantly in the Asian populations. Distinct genotype-phenotype correlations are observable in RNF213-related MMD. The clinical manifestations linked to p.R4810K bear commonalities within Asian cohort, including familial predisposition, earlier age of onset, ischemic episodes, and involvement of the posterior cerebral artery (PCA). However, despite these shared phenotypic characteristics, there is significant heterogeneity in RNF213-related MMD presentations. This diversity manifests as variations across ethnic groups, inconsistent clinical symptoms and prognosis, and occurrence of other vasculopathies involving RNF213. This heterogeneity, in conjunction with the observed low disease penetrance of RNF213 mutations, suggests that the presence of these mutations may not be sufficient to cause MMD, underscoring the potential influence of other genetic or environmental factors. Although the current research might not have fully identified these additional contributors, experimental evidence points toward the involvement of RNF213 in angiogenesis, lipid metabolism, and the immune response. Future research is required to unveil the molecular mechanisms and identify the factors that synergize with RNF213 in the pathogenesis of MMD.

The Role of Dual Antiplatelet Therapy (DAPT) vs Surgery in a Case of Moyamoya Disease: A Case Report and Review of the Literature

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by non-atherosclerotic and non-inflammatory progressive narrowing of the intracranial part of the carotid artery and its proximal branches. The disease process is commonly associated with the development of weak, dilated collateral blood vessels at the base of the brain. This gives it a classic smoky appearance on cerebral angiograms and hence the name "Moyamoya" which means "puff of smoke" in Japanese. When a patient has similar vasculopathy in the setting of another disease then it is known as Moyamoya syndrome (MMS). The associated diseases are sickle cell anemia, neurofibromatosis, long-standing diabetes, uncontrolled hypertension, or chemotherapy. Despite being known as a disease of the East Asian population, the disease is no longer exclusive to Asians, as evidenced by the rising incidence among non-Asian groups such as Caucasians, Hispanics, and African Americans. Patients can remain asymptomatic or present with ischemic or hemorrhagic stroke, headache, seizures, or recurrent transient ischemic attacks. Conventional cerebral angiography is considered the gold standard for diagnosing MMD. Treatment may be supportive, medical, or surgical. We present the case of a 42-year-old African American woman with several comorbidities who presented with sudden onset of ischemic stroke and upon further workup was found to have MMD. Equally important is to identify the most effective therapeutic approaches based on individual patients to achieve better clinical outcomes. Our case report highlights the importance of surgery in symptomatic MMD with a lack of supporting evidence indicating the benefits of dual antiplatelet therapy (DAPT).

Differences in Clinical Features among Different Onset Patterns in Moyamoya Disease

Moyamoya disease is characterized by severe stenosis at the ends of the bilateral internal carotid arteries and the development of collateral circulation. The disease is very diverse in terms of age at onset, onset patterns, radiological findings, and genetic phenotypes. The pattern of onset is mainly divided into ischemic and hemorrhagic onsets. Recently, the opportunity to identify asymptomatic moyamoya disease, which sometimes manifests as nonspecific symptoms such as headache and dizziness, through screening with magnetic resonance imaging has been increasing. Various recent reports have investigated the associations between the clinical features of different onset patterns of moyamoya disease and the corresponding imaging characteristics. In this article, we have reviewed the natural history, clinical features, and imaging features of each onset pattern of moyamoya disease.

Correction: Ethnic variation and the relevance of homozygous RNF 213 p.R4810.K variant in the phenotype of Indian Moya moya disease

[This corrects the article DOI: 10.1371/journal.pone.0243925.].