Extending the GrimAge Epigenetic Clock with Physical Fitness Measures

An aging clock can be built from near any collection of data that changes with age. The first epigenetic clocks used DNA methylation status for many different locations on the genome, but just about any biochemical or physiological measure can be incorporated into a clock algorithm. Since early epigenetic clocks were insensitive to physical fitness, it is interesting to see an attempt to extend a later epigenetic clock by adding assessments of physical fitness. Can there be a hypothetical best clock, one that accurately reflects the result of any intervention in aging, or will it always be the case that clocks will only approximate the complex reality, and there will always be issues in which a clock is too sensitive or not sensitive enough to one or more mechanisms of aging? That is the question. Physical fitness is a well-known correlate of health and the aging process and DNA methylation (DNAm) data can capture aging via epigenetic clocks. However, current epigenetic clocks did not yet use measures of mobility, strength, lung, or endurance fitness in their construction. We develop blood-based DNAm biomarkers for fitness parameters gait speed (walking speed), maximum handgrip strength, forced expiratory volume in one second (FEV1), and maximal oxygen uptake (VO2max) which have modest correlation with fitness parameters in five large-scale validation datasets. We then use these DNAm fitness parameter biomarkers with DNAmGrimAge, a DNAm mortality risk estimate...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs