Comprehensive investigation of RNF213 variants revealed that RNF213 p.Arg4810Lys is strongly associated with ICAS patients in the Japanese population, and identified RNF213 p.Cys118Arg, p.Ser193Gly, p.Val1817Leu, p.Leu2356Phe, and p.Asp3329Tyr as candidate variants associated with intracranial artery stenosis. The gene discussed is RNF213; the disease is familial isolated congenital asplenia.