The average lifespan can probably be extended to 150 years, but "there will always be too little," said the President of Russia. "Doctor Peter" found out what science knows about the factors of longevity and whether aging can be transformed from a fatal process into a manageable project.
Aging is a complex biological process that intertwines genetic programs, lifestyle, and environmental influences. However, in recent decades, genetics has made significant strides: modern research has not only identified genes associated with longevity but has also shown that the structure of DNA reflects the rate of biological aging. We discussed this with physician Marina Stepkovskaya.
Telomeres: The Biological Age Counter
At the ends of chromosomes are telomeres—protective structures that prevent DNA damage during each cell division. Over time, telomeres shorten, and when their length reaches a critical level, the cell loses its ability to divide. This phenomenon—cellular senescence—is one of the main drivers of tissue aging.
Telomere length is partially inherited. Slower shortening is associated with longevity. Telomerase—the enzyme that restores telomeres—is active only in stem and some immune cells, and its excessive activation significantly increases the risk of tumors.
Thus, telomeres serve as a sensitive indicator of the body's condition and one of the most studied markers of biological age.
Longevity Genes
International studies of centenarians have identified several genes that significantly increase the likelihood of reaching the age of 90+.
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FOXO3, which regulates the cellular stress response, metabolism, and immunity. Its favorable variants are found in centenarians more often than in the general population.
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The APOE2 allele protects against cardiovascular diseases and dementia, while APOE4, on the contrary, increases risks.
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SIRT1 and SIRT6 are genes from the sirtuin family. They are involved in regulating energy, inflammation, and DNA repair (restoration after damage or error).
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IGF1 and related pathways control growth hormone and metabolism. Lower activity of these pathways is associated with increased lifespan in several models.
"It is important to emphasize: there is no immortality gene. Longevity is the result of a combination of hundreds and thousands of genetic variations, each of which has a small effect, as well as a lifestyle that supports positive features of the body and mitigates traits that can transform into disease," continues the physician.
DNA Repair: The Quality of Repair Determines the Rate of Aging
Every day, up to a million DNA damages occur in each cell. The effectiveness with which the body eliminates them determines the rate of mutation accumulation and biological aging. Key repair systems include the nucleotide excision pathway (XPA–XPD), double-strand break genes (BRCA1/2), and PARP enzymes activated by DNA damage.
"Mutations in these systems lead to accelerated aging and early age-related diseases. In contrast, centenarians often show increased activity of repair genes or more effective variants of these genes," says Marina Stepkovskaya.
Mitochondrial DNA: Energy and Free Radicals
Mitochondria—the cell's "power plants"—have their own DNA, which is vulnerable to damage. With age, mutations in mitochondrial DNA accumulate faster than in nuclear DNA, reducing the energy potential of cells and increasing oxidative stress.
"Some variants of mitochondrial DNA found in centenarians ensure more efficient functioning of the respiratory chain and lower levels of free radicals. This is another example of how genetics helps determine the rate of biological aging," explains the expert.
Heredity or Lifestyle: Which is More Important
According to modern research estimates, genetics accounts for about 20–30% of variations in lifespan. The rest is due to environmental influences and lifestyle. Thus, predisposition only defines potential.
"The realization of this potential depends on factors that a person largely controls: nutrition, regular physical activity, stress levels, quitting smoking and alcohol abuse, sleep quality, and social activity," explains Marina Stepkovskaya.
Genetic studies of aging have shown that DNA is not just a carrier of information but also a subtle regulator of biological time. Telomeres, repair genes, and mitochondrial DNA form a complex network of mechanisms influencing lifespan.
"But the main discovery of the 21st century is that genetic aging programs are plastic. They can be slowed down through habits, lifestyle, and medical technologies. DNA only determines the starting conditions, while the trajectory of aging is shaped by the individual," notes the expert.
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