Genomic Perspective on Heterogeneity of Organs and Body Aging

Aging is a heterogeneous process, with organ systems and individuals experiencing variable rates of decline that are not fully reflected by chronological age. This variability contributes to the complexity of system morbidity, which poses increasing challenges for clinical care and biomedical research. In this review, we discuss the heterogeneity of organ and whole-body aging and perspectives on genomics as possible mechanisms that relate to such heterogeneity. We discuss how static genomics, including nuclear genetic variants, and dynamic genetics, such as somatic mutations, epigenetic drifts, and mitochondrial DNA changes might explain the variable rate of aging across organ systems and the whole body. We discuss that the use of metrics that capture heterogeneity in organ and body aging is critical to identify genomic biomarkers of aging, clarifying mechanisms of adaptation versus decline.