"Why Do Humans Live Up to 80 Years?"... New Research Results Differ from Conventional Wisdom

Somatic Mutation Frequency Is Inversely Proportional to Lifespan

A new study has revealed the reason why the average human lifespan is generally around 80 years. Photo by Yonhap News

[Asia Economy Reporter Na Ye-eun] A new study has revealed the reason why the average human lifespan is generally around 80 years.

On the 13th (local time), according to The Telegraph, the Wellcome Sanger Institute in Cambridge, UK, stated that the lifespan of a species is determined by how quickly the genetic information contained in deoxyribonucleic acid (DNA) is damaged.

The institute observed the frequency of somatic mutations using stem cells taken from the intestines of 16 animal species, including humans. Somatic mutations, which can occur in all cells that make up the body, sometimes cause cancer or functional disorders but are generally considered harmless.

The most notable finding in this study is that the frequency of somatic mutations is inversely proportional to lifespan.

This result differs from the common belief that larger bodies live longer.

Until now, academia has explained the lifespan difference between the South Asian mouse, which lives for 6 months, and the bowhead whale, which can live up to 200 years, by stating that "smaller animals have faster metabolism and shorter cell replacement cycles, leading to relatively faster aging."

However, there have been many cases that this hypothesis could not explain. For example, the naked mole-rat, which is only 5 inches (12.7 cm) long, and the giraffe, which is over 5 meters long, have similar lifespans of about 24 to 25 years.

Regarding this, the institute explained, "This is because the frequency of somatic mutations is similar, with an annual average of 93 and 99 cases, respectively."

Meanwhile, humans, who live an average of 83.6 years, have a somatic mutation frequency of 47 cases.

The research team stated that these animals showed a pattern of lifespan ending when the cumulative number of somatic mutations reached an average of 3,200 cases.

Dr. Alex Keegan, the first author of this study, said, "The most interesting point is that the rate of somatic mutations is inversely proportional to lifespan," adding, "This suggests that somatic cell division plays a role in aging."

This content was produced with the assistance of AI translation services.