Investigating the function of the proteins encoded by the 12 genes that showed ‘acceptable’ co-segregation (presence in all MS cases and <33% of unaffected individuals)—PLK1, MBP, ITPR3, SORCS1, PRAM1, CACNA1F, MECP2, CPT1A, MTMR7, TRIM66, TTC28, and TOX3—we found that the proteins encoded by these genes could be linked to (de/re)myelination and/or the auto-immune response, as shown in the molecular framework in Figure 1. This evidence concerns the gene PLK1 and myeloid sarcoma.