Figure 3: Association of SNP rs6490029 (CUX2) with the methylation of cg10833066.
From: Methylome-wide Association Study of Atrial Fibrillation in Framingham Heart Study

The boxplot indicates the minimum, 25%, 50%, 75% and the maximum methylation level for each genotype. Outliers were marked as points. Samples with one or two “A” alleles at rs6490029 tended to have a higher methylation level. The number of samples with each genotype was marked as well.