Additionally, researchers have characterized the ubiquitin ligase function of RNF213 in vitro and discovered that mutations in RNF213 associated with MMD can result in a substantial decrease in its ubiquitin ligase activity, which suggests that diminished ubiquitin ligase activity, caused by mutations in RNF213, may contribute to the development of MMD (13). The gene discussed is RNF213; the disease is multiminicore myopathy.