Transplants might hopefully be more easily available in the future, and pigs could become our biggest organ donors after gene cropping, that would at least preserve more lives in need of saving.
- Pig organs function very similar to our own, but are infected with retroviruses (PERVs) that might cause sickness in humans
- Previous researchers manage to eliminate 6 copies of the PERVs
- The new method cropped out 62 copies of the retroviruses
- This could eventually make pig-to-human transplant safe
It’s unfortunate that there is a shortage of human organ donors, even post-mortem. This particular lack costs many lives, but may yet be solved. According to researchers, science might have found a way to improve the chances of patients in need for viable organs. The source? Pigs.
Whole pig organs function very similar to our own, which makes them the best candidate for the job. In fact, pig heart valves are already in use for multiple procedures, as a replacement when the patient’s own heart valve malfunctions. And that is apparently only the first step, though research has been hindered so far.
Even though whole pig organs would be a good match for humans, they are often littered with porcine endogenous retroviruses (PERVs). They are virtually harmless to the animal, but potentially dangerous for humans, as they cannot be cured or neutralized before or after the transplant. This has placed the medical community at an impasse.
However, researchers at the Harvard Medical School, led by George Church, have devised a method to essentially edit out the harmful viruses. CRISPR-Cas9 works like a molecular scissor that can simply trim out the unwanted parts of the pig genome. It could be pictured like a cropping tool in photo editing, by cutting out the unneeded parts of a picture. Of course, on a much, much more complex scale.
Through CRISPR, researchers were able to successfully edit out 62 copies of harmful retroviruses, after previous studies have only achieved the elimination of 6. According to Church, they were able to set a record for gene modification that could see numerous uses in the future.
This could fix one of the biggest problems surrounding porcine-to-human xenotransplantation. It essentially proves that the retroviruses can be eliminated, and that it will not affect human cells. Furthermore, it did not lead to further genome mutation.
However, they were not able to demonstrate just yet that it will make the organs perfectly safe for the receiver. Additional research is pending, but it’s an exciting prospect in the field that gene editing technology has taken such a huge step forward. Apparently, the same technique could be used on human embryos to increase the body’s immune system before birth.
Perhaps, for some though, gene modification is a worrying and disturbing thought, especially if it’s used the wrong way. It has sparked ethical debates among experts, fearful that it would lead to unauthorized experimentation on human DNA.
Image source: nature.com