Expression of mir-15a and miR-16 in 13q intact and 13q−CLL. (A) Structure of dleu2-miR-15a-16-1 and smc4-miR-15b-16-2 genes. (B) Levels of miR-15a as measured by quantitative RT-PCR and normalized to the levels of RNU6B used as a loading control in lymphocytes (total and CD19⁺ B cells) from normal donors and 13q⁺ or 13q− CLL. The data were then expressed as a percentage of the values obtained for one arbitrarily chosen normal set at 1. Each column on the graph is a composite of dot plots showing the actual expression values of miR-15a and a box and whisker plot representing the 90% confidence interval. Statistical analysis was conducted using ANOVA; mean expression of miR-15a was significantly different between normal lymphocytes compared with 13q normal and 13q− CLL (***P < .001), but was not significant between the 2 groups (13q normal vs 13q−) of CLL. (C) Levels of miR-16 as measured by quantitative RT-PCR and normalized to the levels of RNU6B used as a loading control in lymphocytes (total and CD19⁺ B cells) from normal donors and 13q⁺ or 13q− CLL. The data were then expressed as a percentage of the values obtained for one arbitrarily chosen normal set at 1. Each column on the graph is a composite of dot plots showing the actual expression values of miR-6 and a box and whisker plot representing the 90% confidence interval. Statistical analysis was conducted using ANOVA; mean expression of miR-6 was significantly different between normal lymphocytes and 13q normal and 13q− CLL lymphocytes (***P < .001), but was not significant between the 2 groups (13q normal vs 13q−) of CLL.