Learning Why Humans Decline After the Age of 70 Helps Development for New Therapies

Researchers at the Sanger Institute in Cambridge, England, recently discovered that humans’ blood changes drastically as we get older and increases our risk of getting diseases and weakens our immune systems.

The study was published in June 2022 and centered around blood taken from 10 people who ranged in age from newborns to over 80-years-old. The scientists sequenced the genomes to look for differences in the blood of the 10 participants.

It showed that the stem cells they studied mutated an average of 17 times per year after birth and lost roughly 30 base pairs each year from their telomeres, which are regions of repetitive DNA sequences at the end of a chromosome.

The shortening of telomeres can be caused by someone’s lifestyle and is usually seen in people who are aging and are developing age-related diseases.

The study also showed that for people who are 65 and younger, a diverse community of stem cells (20,000 to 200,000) makes up their blood. But for people who are over the age of 65, less than 100 types of stem cells perform that function. By the age of 70, mutated stem cells self-proliferate and cause this lack of diversity.

Basically, this means that the blood of people at this age is coming from a small number of faulty stem cells and the blood is of poorer quality and puts older folks at a higher risk of blood cancers and blood disorders, a higher risk of sickness, and it means recovery will be slower.

But the researchers believe these findings can be used to help older people out in the future.

Dr. Elisa Laurenti, the senior author of the study, said,

“We predict that these factors also bring forward the decline in blood stem cell diversity associated with aging.

It is possible that there are factors that might slow this process down, too.

We now have the exciting task of figuring out how these newly discovered mutations affect blood function in the elderly, so we can learn how to minimise disease risk and promote healthy aging.”

Let’s hope this leads to some positive results and more people living longer lives!