Figure 4. Prediction models of pubertal and biological aging.

(a) Scatter plot of chronological age and pubertal age. Using an elastic net prediction model and a 10-fold cross validation, the pubertal age was predicted from DNA methylation patterns in peripheral blood from (b) boys and (c) girls. A residual error of 0.39 and 0.74 year, equalling five and nine months was observed in boys and girls, respectively. (d) Prediction of biological aging from our data using the same algorithm as applied for pubertal age revealed a residual error of 0.94 year (11 months). The dashed red line is the identity line.