Defining the aging phenotype
Image credit: https://youtu.be/Q1CwARpnfe8
By Shubhankar Kulkarni on Jul 28, 2020
Question: Can we come up with a cumulative age score that can be used as a proxy for aging?
In aging studies, there have been challenges of defining the most relevant phenotype as a comparator. There are differences in the study designs, across study populations or models, and certain genetic effects surface only at extreme ages. Lifespan does not correlate appropriately with the physiological age and hence there is need for another biomarker. Different studies define the aging phenotype differently:
- Number of years free of age-related psychological or physiological disease
- Epigenetic status of the cells
- Telomere length
- Changes in metal isotopes
- Changes in metabolites like NAD+
Can we come up with a cumulative age score based on all these factors or is there any other highly significant factor that can be used as a proxy for aging? We need to normalize aging to something, which can be more of a universal factor that can be used in scientific empirical studies.
If we cannot, what are the reasons?
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