ACTA2 and multiminicore myopathy: conducted a genetic linkage analysis and genome‐wide association study of 20 patients with ACTA2 mutations, showing that patients with mutations in this gene can develop various vascular diseases (including MMD) and pointing out that the underlying mechanism is vascular SMC migration caused by the ACTA2 SD4 domain (p.R258C/H, P.R212) mutation.