KIF21B and myeloid sarcoma: Kif21b mRNA expression was assessed in the white matter of 11 NDC and 16 MS patients (Additional file 1: Table S3) and we found that kif21b was approximately ten-fold increased in MS compared with NDC (median and IQR of kif21b expression relative to GAPDH in NDC 0.037, 0.006-0.34 vs. MS 0.36, 0.17-0.34, p = 0.03, Figure 5).