A recent case-control study performed in a Slavic population (Croatia, Serbia, and Slovenia) reported the association with MS risk of two single nucleotide polymorphisms (SNPs) [6]: rs3789327 in ARNTL (OR = 1.67 [1.35–2.07], p = 0.0001) and rs6811520 in CLOCK (OR = 1.40 [1.13–1.73], p = 0.002). The gene discussed is CLOCK; the disease is myeloid sarcoma.