Using WES, signatures attributed to three mutational processes have been detected in MM: (1) APOBEC3-specific signature, sometimes with mutation clustering, kataegis; (2) SHM-like mutations (in C-T pairs and A-T pairs), often clustered; and (3) C->T mutations in CpG motifs, age-associated signature found in many cancers that are caused by deamination of methylated cytosine, which is generally considered to be spontaneous, but can also be AID-mediated [29,456,467]. The gene discussed is AICDA; the disease is Miyoshi myopathy.