MYD88 and Miyoshi myopathy: We additionally considered all 19 individuals (10 WM and 5 IgM MGUS from WM families, 4 MGUS from MM families) identified above with significant MYD88 L265P mutation allele fractions and performed deep Ion Torrent-based sequencing (mean read depth 18,000X) in DNA extracted across three time points: from blood prior to EBV-immortalization (0p), from LCLs after 4 passages in vitro (4p) and 9 passages in vitro (9p), with the 9p points repeated for a subset of 13 samples.