Besides MMD, the RNF213 Arg4810Lys variant can impact multiple vascular dysfunctions, including intracranial artery stenosis (ICAS), intracranial artery stenosis/occlusion disease (ICASO), quasi-Moyamoya syndrome (MMS), and adult-onset ischemic stroke. The gene discussed is RNF213; the disease is familial isolated congenital asplenia.