Published: Fri, August 11, 2017
Medicine | By Megan Pierce

Your future organ donor might be a pig, study suggests

Your future organ donor might be a pig, study suggests

Unless the pig organs are edited to also be more compatible for human bodies, it'd be too risky to transplant them into people.

In new studies that demonstrate how quickly genetics science is advancing, researchers used the Crispr gene-editing system to make long-sought alterations in animals, with potential relevance for human health.

If pig organs were shown to be safe and effective, "they could be a real game changer", said Klassen, who was not involved in the new study.

"Porcine organs are considered favorable resources for xenotransplantation since they are similar to human organs in size and function, and can be bred in large numbers", they wrote in astudy published Thursday in the journal Science. "We don't know that if we transplant pig organs with the viruses that they will transmit infections, and we don't know that the infections are risky", he tells the Times. The viruses the researchers targeted, which dwell in pig DNA and can be passed down during transplantation and infect human cells, have been another concern.

Researchers in the U.S. used the precision gene editing tool Crispr-Cas9 combined with gene fix technology to deactivate 100% of Pervs in a line of pig cells. As the New York Times reports, researchers have wanted to explore using pigs as organ sources in the past, but plans were thwarted by the fear that viruses from the pigs, called retroviruses, could infect humans through the transplants. Pig heart valves already are routinely transplanted into patients. While most major religious groups say pig organs are acceptable in the case of lifesaving transplantation, one example that could be a problem for Jewish and Muslim patients is accepting a kidney transplant, because dialysis is a viable alternative. The presence of these PERVs means pig organs can not now be safely transplanted into humans.

In particular, the pig genome is known to carry porcine endogenous retroviruses (or PERVs), which are capable of transmitting diseases, including cancers, into humans.

These baby pigs were the first to be born without innate viruses in their DNA. In any event, said Dr. A. Joseph Tector, a transplant surgeon at the University of Alabama Birmingham, pig retroviruses are very sensitive to the drugs used to treat HIV. They allowed each egg to develop into an embryo and implanted it in the uterus of a surrogate mother. Now, without the threat of these hidden diseases, it may be possible to safely transplant pig livers, hearts, and other organs.

The study was partly funded and conducted by the biotech company eGenesis.

Every day, about 22 people die because they don't get the replacement organs they desperately need.

Doctors and scientists have been searching for the holy grail of organ replacement-a way to grow usable organs outside the human body-for decades.

Formidable obstacles remain "in overcoming immunological rejection and physiological incompatibility of pig organs in humans", he said.

Like this: