Specifically, host genetic susceptibility (i.e., HLA-DRB1*15 allele group), biomarkers such as IL-17, chitotriosidase, and antibodies against fungi and the administration of the disease-modifying drug, dimethyl fumarate, for the treatment of MS (which, incidentally, can suppress molds) collectively suggest there could be a fungal etiology of MS (Benito-León and Laurence, 2017). This evidence concerns the gene IL17A and myeloid sarcoma.