A man in Maryland has received a pig heart transplant. What an interesting idea! People have been talking about xenotransplants of this magnitude for decades, and now someone actually gets to try it. It’s also a terrifying idea.
- My first thought was of Baby Fae, the infant in 1984 who received a baboon heart. It was a disaster. The surgeon didn’t believe in evolution and dismissed concerns about the degree of relatedness, and the donor was blood type AB and Fae was type O. They also didn’t have any means of genetically modifying the baboon. Would you believe there are ethical concerns and responsibilities in this sort of thing?
- The Washington post article is all about the ethics of the surgery, which is good. It takes a really cock-eyed perspective, though: the recipient was a bad guy who stabbed and paralyzed someone, failed to pay court-ordered compensation to his victim, and also has a history of being sloppy and undisciplined about his medications. Should he have been given this gift?
Jesus, it’s not even in question. Doctors should deliver health care based on need, not passing judgment on the worth (in all senses of the word) of their patient. What next? Will doctors decide on my treatment based on my credit score? Yeah, you don’t have to tell me that here in the good ol’ USA that is the de facto situation. It’s not good.
- For the retribution crowd, relax. He is being punished. He’s an experimental guinea pig for a treatment that’s going to buy him a little time. The pig was extensively manipulated with 10 genes modified to reduce, but not totally eliminate, the chance of rejection. He’s going to be trapped in a hospital bed for a good long while, with nurses waking him up every few hours through the night to do blood tests, and he’s going to be taking so many pills. I’ve been in that place for relatively trivial surgeries, it’s a necessary hell. Have a little pity.
- He’s probably going to die in a few months, anyway — I’ll be surprised if his new heart isn’t shredded by rejection in short order. I’ll be pleasantly surprised if he gets a significant survival time, though, since that means this could be a very promising treatment for everyone.
- Except the pigs. You do realize that this implies the existence of pig farms for animals whose fate is to be chopped up as needed for organs, right? It’s a tiny drop in the slaughterhouse bucket, since humans butcher 1.5 billion pigs per year to make pulled pork sandwiches and bacon, so it’s not the numbers that are daunting, it’s the fact that right now there are cloned pigs being modified and raised in artisanal farms in the hopes that genetic refinement will make them incredibly valuable to corporations. These are long term investments!
- No one is talking about how much these expendable pigs cost. We aren’t talking about the ethics from the pig’s perspective, and we’re suspiciously mum about what the bill is going to be. This lucky (?) fellow in Maryland is benefitting from a bit of scientific curiosity — hey, we’ve been raising all these special pigs for a decade or so, how about if we splice one heart into a test subject and see what happens — but if it works and becomes a relatively routine intervention, who’s going to be able to afford it?
- While I’m on the pig’s side, what do these gene modifications do to the health of the pig stock? Does this compromise their immune systems? Are these going to be bubble-pigs that need to be raised in a sterile environment?
- I got to wondering about the scientific methodology behind making pigs with all these genetic modifications. Here’s an article on practical approaches for knock-out gene editing in pigs. It’s a multi-step, multi-generational process to produce pigs with specific mutations. Scientists have been working for years to make these pigs.
- The above article describes the mechanics, but not the research that goes into discovering candidate genes to reduce the immune response. Everyone is fumbling forward in the dark, finding likely genes that are affecting rejection, but they have to put that pig donor tissue in a human host to see if they actually got ’em all. This man in Maryland is very much a wildly experimental test subject, a scientific experiment in progress. The most likely result is they’ll find that “oops, we missed an important gene” and they’ll go back to the pig farm with a new CRISPR/Cas target and raise another generation with 11 modified genes for the next attempt. Meanwhile, this host is dead. But he will have contributed to Science with his demise!
Anyway, my brain is currently split between a Frankensteinian fascination with this bold experiment, and a humane dismay at the cost in suffering for humans and pigs.