There is significant overlap between these theories and even categories of aging theories.
Our genes can be envisioned as a series of letters that make up words and sentences of instructions.
These words and sentences code for the manufacturing of proteins that control every cellular process.
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If a mutation occurs in proteins that regulate the growth of a cell, cancer may result.
People whose parents and ancestors have lived longer, tend to live longer and vice versa.
At the same time, we know that genetics alone are not the sole cause of aging.
Some genes are beneficial and enhance longevity.
Some gene mutations are inherited.
Mutations also can happen after birth, since exposure to chemicals and radiation can cause gene changes.
(Gene mutations acquired after birth are referred to as acquired or somatic gene mutations.)
Most mutations are not bad for you, and some can even be beneficial.
That’s because genetic mutations create genetic diversity, which keeps populations healthy.
Other mutations, called silent mutations, have no effect on the body at all.
Some genes, when mutated are harmful, like those that increase the risk of cancer.
Many people are familiar with the BRCA1 and BRCA2 mutations which predispose to breast cancer.
Various diseases and conditions related to heritable gene mutations can directly impact lifespan.
These include cystic fibrosis and sickle cell anemia, to name a couple.
Each time a cell divides a little more of a telomere is snipped off.
In addition, some cells such as white blood cells do not undergo this process of telomere shortening.
Longevity Genes
Longevity genes are specific genes that are associated with living longer.
Cell Senescence
Cell senescence refers to the process by which cells decay over time.
An example of a tissue jot down in which regeneration is possible by this method is the liver.
Epigenetics
Epigenetics refers to the expression of genes.
In other words, a gene may be present but can either be turned on or turned off.
When looking at genetic theories, these are broken down into three primary schools of thought.
In addition, we are finding evidence for some of the specific mechanisms involved in the genetic theory.
Why would there be a specified lifespan beyond reproduction?
It’s also important to note that the theories discussed here are not mutually exclusive.
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