Life expectancy advancements raise health and safety concerns
The race to increase life expectancy gained momentum with a recent study. Genetic reprogramming was used to increase the life of mice by 7%, according to Rejuvenate Bio, a biotech company in San Diego. The mice were 124 weeks old, comparable in age to a 77-year-old human.
The control group lived for roughly nine weeks after the study began. The genetically-reprogrammed mice lived for about 18.5 weeks. The life expectancy for mice is 129 weeks, meaning the reprogrammed mice lived 7% longer than expected, the equivalent of five years for humans.
Dr. Melissa Antonio, associate professor of biology, explained that genetic reprogramming is able to slow down the aging process due to its ability to “reset” differentiated cells to a stem-cell-like state.
“The process of genetic reprogramming involves epigenetics, where methyl groups are added to specific gene loci along the DNA, causing those genes to not be expressed, while other genes that are not methylated remain expressed,” Antonio said.
Epigenetics is a branch of genetics that analyzes how our environment affects our genes. Scientists study these effects with methylation, the addition of a methyl group to our DNA. When a methyl group is added, it condenses our DNA preventing the gene from being expressed. The genes without methyl groups are more easily expressed.
This process can be applied to genes related to aging, creating the potential for increased life expectancy. However, the dedifferentiation of cells leaves them vulnerable to unwanted changes that could lead to
“Introducing cells that have lost their differentiated fate for anti-aging purposes in animals can lead the cells’ genome to becoming more vulnerable to changes that would cause them to grow uncontrollably,” Antonio said.
When cells are genetically altered, there is an increased risk of cancer. At the cellular level, cancer is caused by unregulated growth due to genetic mutations.
It is unclear what side effects, if any, were present in the reprogrammed mice. The study conducted by Rejuvenate Bio has yet to be peer-reviewed and contained limited documentation on the cells that were reprogrammed.
Genetic reprogramming continues to draw attention from the scientific community despite its risks. Antonio explained that extending life expectancy has consequences, whether prolonged existing diseases or the development of additional health-related
“It’s a beautiful intellectual exercise, but I would shy away from doing anything remotely similar to a person,” said Vittorio Sebastiano, professor at Stanford University, in an interview with Technology Review.
Aging is a natural process characterized by chronic disregulation of cellular mechanisms. This in turn leads to tissue and organ deterioration. Messing with our body’s natural development can have unforseen consequences.
“We should not be pursuing any method to increase life expectancy because it can cause major problems that are more catastrophic than helpful,” said Valeria Molina, senior biomedical science major. “Who are we to increase life expectancy?”
Looking beyond the medical ramifications, Antonio turns to her faith when examining the consequences of an extended life expectancy.
“Spiritually speaking, we must keep in mind that this is a fallen world we live in, full of suffering and increasing life expectancy is just going to prolong the suffering we bear in this world,” Antonio said.
“There is a reason God has limited our time here and I am against the idea of ‘playing God’ and changing our DNA, for example, in order to live longer. I prefer to leave our life in his hands.”