With regard to the risk group, the analysis of saliva IL-2 levels in ill children showed a statistically significant correlation between the average value for this cytokine and the risk group of children with ALL in study 1 (Spearman’s rank correlation coefficient = 0.5546, t = 2.4941, p = 0.0258) and in study 2 (Spearman’s rank correlation coefficient = 0.3988, t = 2.4983, p = 0.0176). This evidence concerns the gene IL2 and acute lymphoblastic leukemia.