These results are in line with previously mentioned studies (Villar et al., 2005, 2008; Owens et al., 2009) and with studies showing an association between IgM with a severe MS course, according to both clinical and MRI outcomes (Villar et al., 2003, 2005;Ozakbas et al., 2017). This evidence concerns the gene CD40LG and myeloid sarcoma.