Moyamoya disease is a rare cerebrovascular disorder with unknown aetiology. It is characterised by progressive narrowing of arteries of the brain and the formation of a compensatory network of fragile vessels. Genetic studies have identified RNF213 (also known as mysterin) as a susceptibility gene but the low penetrance in genetically susceptible individuals suggests that a further factor is necessary to trigger disease onset.1
This is a companion discussion topic for the original article at https://patient.info/doctor/neurology/moyamoya-disease.htm