Extending human life through leveraging gene editing
If you were the average person born in the 1960s, your life expectancy would be a mere 53 years. Fast forward half a decade to today, the average is a whopping 72 years of age. On the surface level, this looks like an immense increase in human life — a spectacular display of our medical and technological progression. What’s even more surprising? This number is unimaginably deceiving.
If you go deeper into the data, you’ll find that the miracle of modern medicine hasn’t increased the human lifespan whatsoever — it’s only prevented premature death at a large scale. Vaccines haven’t extended the lifespan of a single person — they’ve only prevented life-shortening diseases from harming humans. Even if we look all the way back to the 1600s, Isaac Newton died at an astonishing 84 years of age, which is 12 years higher than the average right now!
Fortunately, the next evolution of technology has finally dawned upon us. CRISPR CAS9 is a gene editing tool inspired by the way in which bacterium defend themselves against invading viruses. The system serves as a genetic memory of previous invaders that help the bacteria detect weaknesses and destroy viruses when they return.
CRISPR spacer sequences are transcribed into short RNA sequences capable of guiding the system to matching sequences of DNA. When the target DNA is found, Cas9 — an enzyme produced by the CRISPR system — binds to the DNA and cuts it, shutting the targeted gene off. CRISPR can then precisely insert engineered DNA into an organism.
This is where the extending human life piece comes in. Every time your cells multiply, they copy each other’s chromosomes. Because of the nature of this system, they lose bits of DNA at the end of the helix. To protect themselves from damage, they have long strands of DNA called telomeres that act as protection for the choromosone. Unfortunately, these shields deteriorate with every cell division. After the telomere has been completed eradicated, some cells become senescent cells, zombie-like cells that underproduce protease. Because of this abnormality, senescent cells are programmed to die and cause damage to tissue around it, cause diseases such as kidney failure and diabetes, and are increasingly being called the root of aging by scientists globally.
When scientists genetically engineered mice to be capable of killing off their senescent cells, they received some shocking results. These mutated mice had better kidneys and hearts and were less prone to cancer. So how do we do it, you ask? Simple; we genetically modify our cells to produce more more protease. In this fashion, normal cells will not change in behaviour and senescent cells will die when damaged. In another study where scientists genetically engineered mice to produce more protease in their body, they found that the mice grew back lost hair and lived 30% longer than their peers.
A number of companies today such as Unity Biotechnology, Klogene, Cardax and more are researching and developing in the human lifespan/healthspan field. What’s amazing is that this is the only the beginning, as well. The possibilities for the future are truly limitless.
