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The Aging Error Catastrophe theory suggests that copying errors in DNA and protein synthesis cause catastrophic aging, but it has been largely rejected due to the high fidelity of DNA copying mechanisms. The theory also does not apply to viruses, as their mutation rates are too low to cause failure catastrophes.
The Aging Error Catastrophe, originally proposed by Leslie Orgel in 1963, argues that copying errors in DNA and the misplacement of amino acids in protein synthesis could aggregate over an organism’s lifetime and ultimately cause catastrophic failure in the form of obvious aging. Experimental tests that have attempted to determine differences in the nucleotide sequences of specific age-related proteins have always failed, so the theory has largely been rejected.
Copying errors have been selected for extremely strongly in the course of evolution because genetic material is the most evolutionarily important part of the whole organism and the organism can in fact be seen as a “survival machine” for the genetic material. In vertebrates, evolution has had to contend with the most negative consequence of imaginable copying errors – cancer – and therefore has DNA copying mechanisms that operate at extremely high fidelity. Because these mechanisms are so finely tuned, the aging fallacy catastrophe, while an interesting theory, is not a real phenomenon.
Sometimes the phrase “mistake catastrophe” is used to refer to smaller organisms, such as viruses. The failure catastrophe in viral populations is similar to the failure catastrophe of aging, but with respect to virions rather than cells. But similar to the failure catastrophe of aging, the failure catastrophe in viral populations cannot be convincingly demonstrated. A given virus has a given genome, and if the mutation rate among viruses were so high that the entire species went bad, then such viruses wouldn’t exist in the first place. It also contradicts the idea that a specific genome is associated with each virus species, which has been experimentally proven to be true.
Through mathematical calculations, we can determine mutation rates that would cause error catastrophes if they were the true values, but they aren’t. All viruses and all human cells can be shown to have mutation rates that are significantly lower than they might predict that a failure catastrophe will eventually occur. The aging fallacy catastrophe is thus a discredited theory, but the means to discredit it is an important educational story for biologists and geneticists.
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