What should we think of DNA experiments and developments?
Jim ponders the most recent developments in the realm of gene editing and asks how Christians should be thinking about them.
For the last several weeks I’ve been intending to write a post reflecting on the latest announcement of what we’re able to do with DNA. But every time I started to write, I came across another of these announcements. Keeping up with the field can be overwhelming. But we can’t let the volume of information keep us from thinking seriously about deeper issues that are involved with these technological advances.
Science is great at figuring out what we CAN do, but not so good at determining what we OUGHT to do. And the church has not always been great at being involved in important cultural conversations while they are still developing. We’re much better at reacting to situations after the fact. How can we do better?
There are some Christians in prominent places, whose voices are taken seriously on these topics. Francis Collins is chief among them, and he has faithfully turned his five talents into five more (Matthew 25:19-21). The rest of us do not have his platform, but we do have influence in own networks. Let us not be afraid and bury our talents in the ground!
Our faithfulness in this area starts with being aware of the latest developments. I offer here a recap of some of those, along with some thinking out loud. Hopefully that will spur you to think about them too. And perhaps we should start by discussing on the Forum.
We’re coming up on the one year anniversary of the announcement that Chinese scientist He Jiankui edited the DNA of two human embryos using CRISPR. The embryos were implanted and twin girls were born who were supposed to be more resistant to acquiring the AIDS virus—a genetic ability they will pass along to their offspring.
The inheritance of these genetic edits is a key concern in the ethical debates about the practice. It is one thing to get consent from someone to change their DNA when it affects only themselves—like in this amazing story of a genetic cure for Sickle Cell Anemia. But it is quite another thing to say we’re going to alter the DNA of someone’s germline now, and these changes will be passed along to all future generations.
Now maybe someone will argue that if we can fix a genetically-inherited disease, why is it a problem to fix that for future generations too? It might even be claimed that it would be an ethical problem if we had the ability to fix it and we chose not to.
That may be an issue we’ll have to confront some day. But we’re not there yet. Very rarely is a genetic issue so straightforward as simply editing one or two “letters” in a gene. Things are much more interconnected, and we just don’t know enough yet to understand what possible ramifications there might be to changing something around. Sad case in point: one of the recent stories about these twins is that the scientist may have inadvertently reduced their life expectancy [update]. Furthermore, it appears that there is no enhanced resistance to AIDS in at least one of the twins.
There is strong consensus in the scientific community that it was irresponsible and unethical to proceed the way he did with editing these kids’ DNA. Here is an article that describes what all went on behind the scenes and who knew what and when. The article includes some comments from William Hurlbut, a Stanford bioethicist and friend of BioLogos. He had interacted with the Chinese scientist and feared this was the path he was going down. Hurlbut gave a longer interview on the topic editing embryos.
Getting close to Gattaca?
If you’d rather listen to people discussing this issue, RadioLab did a recent podcast episode on developments that could allow embryos to be screened for potential intelligence. Again, there are disagreements about how well we understand the genetic basis of intelligence. But these kinds of issues which were purely science fiction when Gattaca came out in 1997 are now serious matters of discussion.
To be clear, this is not yet the kind of situation where you custom order your baby. Rather, for people doing In Vitro Fertilization, more embryos are often produced than will be implanted. In these cases there are choices to be made about which embryos to implant. If those can be genetically screened for certain traits, should we use that information? We are already deciding that some will live and some will not; should we just do this randomly?
These are serious and concerning problems. I strongly recommend watching the plenary talk of Jeff Hardin at the BioLogos conference last spring. He urges that when there is some ambiguity about the status of embryos, the best course of action is caution.
The problem of chimeras
It is very difficult to slow down technological progress in the name of ethical concerns—particularly because there is no single governing body with authority over all scientists. In the United States there are regulations, but not so much in some other countries.
For example, earlier this year Japan lifted a ban on allowing chimera embryos to develop past 14 days. A chimera is a hybrid organism made up of cells from different species. One of the goals of this research is to see if animals like pigs or sheep might be used to grow human organs that could be transplanted in humans. Perhaps in the future we will be able to take cells from an adult human who needs a new heart, reprogram them as stem cells, and then introduce them into a pig embryo which has been genetically altered to lack a gene necessary for heart development. Then, since the pig can’t grow its own heart, it will use the human cells to grow a human heart, which might be a perfect match for the person who needs it.
Do we know, though, whether those human cells will stay confined to the heart? What if some are co-opted into the central nervous system of the pig? What kind of creature would it be if it has human cells in its brain? We can’t answer these questions without experiments, but should we conduct such experiments? Japan says yes.
Japanese scientists are testing this technology first with rat embryos, and have said that if they find human cells in more than 30% of the rodent brains, they will stop the experiment. Is this comforting?
Other scientists in China are not worried about some human cells ending up in the brains of other species. In fact they are purposely looking to develop human-monkey chimeras in order to study neurological and psychiatric diseases in humans. So far that has been limited to introducing human genes for brain development into the DNA of monkeys. Technically, that is not the same as creating a chimera (it is called “transgenic”), since human cells were not introduced, but the scientists claimed that the monkeys with this gene do exhibit improved short-term memory and reaction times compared to the control set.
Where will this kind of research go? There would definitely be important and useful information gained from experiments on brains with human cells. Perhaps we could develop more effective treatments for Alzheimers or other brain diseases, and thereby relieve a vast amount of human suffering. But does the end justify the means? How much of a monkey brain could be replaced with a human brain before we are experimenting on humans and treating them as disposable?
A British developmental biologist has an answer: “If you just swap the hippocampus, it doesn’t mean you are now going to have a human-functioning brain. It might have perhaps slightly better memories or slightly different memories… but they are not going to have a human cortex, which is what actually makes us human.”
That is frightening to me. Can such lines really be drawn so confidently between human and non-human? That kind of reasoning could easily be used to create a class of almost-but-not-quite humans to supply us with organs, or maybe do the menial tasks that don’t require much human intelligence. Is this the Brave New World our scientific prowess will take us to?
It is not just Christians with religious objections who are concerned about these issues. But we of all people ought to be speaking up on behalf of “the least of these.” Christians won’t all agree on just which of these chimeric and transgenic entities count as the least of these, nor will we always agree on the proper public policy regarding the manipulation of DNA and embryos. But let’s at least be involved in thinking and talking about these issues with all the graciousness we can muster, and with urgency before it is too late to have any voice.
This article was updated 10/14/19 to link to a new study about the CRISPR babies.