Aging and mortality: Manifestations of increasing informational entropy of the genome?

Abstract

Information theory has provided insight to the means by which organisms maintain life against the inevitable influence of the second law of thermodynamics. The low entropy content of genetic information is used to harness the energy that an organism in an open system must utilize to maintain its low entropy and life. Redundancy lowers informational entropy, enhances meaning and promotes complexity. The genome is characterized by large quantities of ‘redundant’ DNA. Longitudinal Gompertzian analysis has shown that ‘the rate of loss of vitality’ (from the Strehler-Mildvan modification of the Gompertz model of aging and mortality) has remained constant for general and disease-specific mortality. Applying the concepts of information theory to aging and mortality suggests that ‘the rate of loss of vitality’ may be synonymous with the rate of degradation of redundant genetic information (or alternatively, the rate of increase in informational entropy of the genome). This interpretation is consistent with the hypothesis that genetic instability of repeated DNA sequences may be fundamentally related to the process of aging. Consequently, there may be no specific aging or ‘death’ genes per se, but rather aging and mortality are the inevitable natural consequence of increasing informational entropy (decreasing redundancy) contained within the genome.