However, p.R4810K displays a strongly reduced penetrance since the incidence rate of MMD (e.g., 1/10,000 in the Japanese population) is much lower than the population p.R4810K carrier frequency (e.g., 1/50 Japanese carry the RNF213 R4810K risk allele)96. Here, RNF213 is linked to multiminicore myopathy.