Epigenetic Clock Training Metrics
There are two types of epigenetic clocks – first and second-generation. First-generation clocks use raw or log-transformed CA53 as the dependent variable, whereas a composite measure of aging is the dependent variable in second generation clocks. For the composite measure, “proxies” of biological aging, such as markers of heart and kidney function, are used in addition to CA66. These clocks are described in detail below.