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The mutation accumulation theory of aging was first proposed by Peter Medawar in 1952 as an evolutionary explanation for biological aging and the associated decline in fitness that accompanies it. [1] Medawar used the term 'senescence' to refer to this process.
The somatic mutation theory of ageing states that accumulation of mutations in somatic cells is the primary cause of aging. A comparison of somatic mutation rate across several mammal species found that the total number of accumulated mutations at the end of lifespan was roughly equal across a broad range of lifespans. [16]
Biogerontology should not be confused with geriatrics, which is a field of medicine that studies the treatment of existing disease in aging people, rather than the treatment of aging itself. There are numerous theories of aging, and no one theory has been entirely accepted.
The DNA damage theory of aging proposes that aging is a consequence of unrepaired accumulation of naturally occurring DNA damage. Damage in this context is a DNA alteration that has an abnormal structure. Although both mitochondrial and nuclear DNA damage can contribute to aging, nuclear DNA is the main subject of this analysis.
Strength of natural selection plot as a function of age. The antagonistic pleiotropy hypothesis (APT) is a theory in evolutionary biology that suggests certain genes may confer beneficial effects early in an organism's life, enhancing reproductive success, while also causing detrimental effects later in life, contributing to the aging process.
Aging by design theory; ... Genetic mutation theory of aging; I. ... Waste product accumulation theory of aging; Wear and tear theory of aging
Senescence (/ s ɪ ˈ n ɛ s ə n s /) or biological aging is the gradual deterioration of functional characteristics in living organisms. Whole organism senescence involves an increase in death rates or a decrease in fecundity with increasing age, at least in the later part of an organism's life cycle.
The model developed by Medawar states that due to the dangerous conditions and pressures from the environment, including predators and diseases, most individuals in the wild die not long after sexual maturity. Therefore, there is a low probability for individuals to survive to an advanced age and suffer the effects related to aging.