The systematic review of the literature and meta-analysis performed in the present study on all relevant data revealed significant protective roles of SNPs in pri-miR-34b/c and miR-100, whereas predisposition to B-ALL was associated with SNPs in DROSHA, miR-449b, miR-938, miR-3117 and miR-3689d-2 genes (Figure 2). This evidence concerns the gene DROSHA and precursor B-cell acute lymphoblastic leukemia.