Quasi-moyamoya disease (QMMD) is moyamoya disease (MMD) associated with additional underlying diseases. Although the ring finger protein 213 (RNF213) c.14576G>A mutation is highly correlated with MMD in the Asian population, its relationship to QMMD is unclear. Therefore, in this study the authors sought to investigate the RNF213 c.14576G>A mutation in the genetic diagnosis and classification of QMMD.

This case-control study was conducted among four core hospitals. A screening system for the RNF213 c.14576G>A mutation based on high-resolution melting curve analysis was designed. The prevalence of RNF213 c.14576G>A was investigated in 76 patients with MMD and 10 patients with QMMD.

There were no significant differences in age, sex, family history, and mode of onset between the two groups. Underlying diseases presenting in patients with QMMD were hyperthyroidism (n = 6), neurofibromatosis type 1 (n = 2), Sjögren’s syndrome (n = 1), and meningitis (n =1). The RNF213 c.14576G>A mutation was found in 64 patients (84.2%) with MMD and 8 patients (80%) with QMMD; no significant difference in mutation frequency was observed between cohorts.

There are two forms of QMMD, one in which the vascular abnormality is associated with an underlying disease, and the other in which MMD is coincidentally complicated by an unrelated underlying disease. It has been suggested that the presence or absence of the RNF213 c.14576G>A mutation may be useful in distinguishing between these disease types.

准烟雾病（QMMD）是与其他潜在疾病相关的烟雾病（MMD）。虽然无名指蛋白 213 ( RNF213 ) c.14576G>A 突变与亚洲人群中的 MMD 高度相关，但其与 QMMD 的关系尚不清楚。因此，在本研究中，作者试图研究RNF213 c.14576G>A 突变在 QMMD 的基因诊断和分类中的作用。

这项病例对照研究在四家核心医院中进行。设计了一种基于高分辨率熔解曲线分析的RNF213 c.14576G>A突变筛选系统。在 76 名 MMD 患者和 10 名 QMMD 患者中调查了RNF213 c.14576G>A的患病率。

两组在年龄、性别、家族史和发病方式方面无显着差异。QMMD 患者的基础疾病是甲状腺功能亢进症 (n = 6)、1 型神经纤维瘤病 (n = 2)、干燥综合征 (n = 1) 和脑膜炎 (n = 1)。RNF213 c.14576G >A 突变在 64 例（84.2%）MMD 患者和 8 例（80%）QMMD 患者中发现；队列之间没有观察到突变频率的显着差异。

有两种形式的 QMMD，一种是血管异常与潜在疾病有关，另一种是 MMD 巧合地并发有不相关的潜在疾病。有人提出，RNF213 c.14576G>A 突变的存在与否可能有助于区分这些疾病类型。