Figure 2

Determination of a threshold for the CpG → TpG/CpA substitution rate by a decision tree. CGIs with a methylation level of ≥80% in human sperm cells are depicted by a light blue box labeled HM, and CGIs with a methylation level of ≤20% in human sperm cells are indicated by a the blue box and labeled as LM. In each node of the tree, either label (HM or LM) is assigned to the greater number of CGIs as described under the two boxes (light blue and blue). CpG → TpG/CpA substitution rate ≥0.03825 shows a CpG → TpG/CpA substitution rate of ≥0.03825. CpG → TpG/CpA substitution rate <0.03825 denotes a CpG → TpG/CpA substitution rate of <0.03825.