Like most blockbuster sci-fi, the X-Men franchise stretches the limits of actual science. But the movies’ title sequences always pay tribute to the real genetic research that has given rise to their stories. In the new film, X-Men: Days of Future Past, the opening credits showcase an array of elaborately colored and animated twisting strands of DNA. (X-Men: First Class opted for a simpler, but equally scientific-themed sequence). But aside from these slick CGI nods to DNA sequencing and mitosis, do the X-Men films tell us anything substantive about the science of genetics?
Sloan Science and Film asked Dr. Carla L. Easter, the Deputy Chief of Education at the National Human Genome Research Institute, about what X-Men’s super-mutants can teach us about the everyday genetic mutations that take place in regular humans, how an X-Gene anti-serum might work, and how the process of evolutionary natural selection probably moves too slowly to save our species.
Sloan Science and Film: Can you talk about how you use the X-Men films to teach students about genetic mutations?
Carla L. Easter: I spend a lot of time teaching genetics to high school students and oftentimes, the word “mutant” becomes a very negative term. They often have the sense that everyone is genetically perfect, except for those people who suffer from diseases like cystic fibrosis and Huntington’s disease. But the reality is that we are all mutants; none of us have the perfect genome. And there are certain adaptive types of mutations that are very helpful to us.
SSF: Can you describe how genetic mutation works?
CE: When we think about gaining mutations, there are mutations that we get through external forces, such as UV radiation. But inherently, in the replica of the genome, mistakes occur and they cause mutations. We refer to these as single-point mutations. Most mutations that occur don’t have any effect. But when they occur in a particular place in the genome, they can manifest themselves in the form of some kind of disease. For example, you get a mutation in the gene for hemoglobin that causes sickle cell disease, or you get a mutation in the CFTR gene, which gives you cystic fibrosis. These are the typical mutations that we frequently talk about. When we start to talk about complex disorders, such as certain cancers or high blood pressure or heart disease, there may be mutations or variations within those particular genes that have an impact on the manifestation of these disorders that we have yet to pinpoint. I think it’s important for people to understand that throughout our DNA there are multiple variations. Sometimes, mutations aren’t just changes in nucleotides, so it’s not just a change from an A to G or a C to a T, necessarily. Sometimes you have deletions or insertions, or even deletions of whole pieces of DNA. This idea of a mutation can take multiple forms. And oftentimes mutations take place within other regions of the genome that we don’t even know about.
SSF: So to clarify: when these deletions or insertions come up, it doesn’t necessarily manifest itself in ways that alter our functioning?
CE: Yes, all of us carry mutations. At last count, I think there are some 3 million variations between one person and another. And yes, sometimes, you’d only see them if you sequenced the genome.
SSF: In the film, the mutants inject themselves with a serum that suppresses their mutations. Is there any scientific truth to this idea that we could put something in our body that would alter our genetic makeup?
CE: To alter your genetic makeup? No. That would involve altering every cell involved in our bodies. Although we are getting better at gene therapy, you’re talking about altering something in a more permanent way. But suppressing it is a different question. We do have medications that control particular things. I imagine you could take some sort of therapeutic that could counteract the result of a mutation. With cystic fibrosis, for example, one of the major issues is the production of mucous, which causes a lot of trouble. So the ability to suppress mucous production would be the suppression of the symptoms, but not necessarily an altering of the genetics. Maybe that’s how the serum works.
SSF: I was reading about a recent study that suggested the number of mutations found in the human populace are actually increasing and are becoming more dangerous. Do you know anything about this research?
CE: I don’t, but there’s an interesting project called the Resilience Project, which is the being done by researchers to look for mutations that actually help people. For instance, if you have a mutation in the gene that causes cystic fibrosis, why don’t you suffer from the disease if you have the mutation? So there are people who have gained mutations over time that have been passed on and are protective in certain ways.
SSF: Can you talk about other positive mutations?
CE: One of the places to look at is adaptability to altitude: the Sherpas in the Himalayas, for example, are individuals who have become adaptive to high altitudes. There seems to be an adaptive response to this and there seems to be some genetic predisposition to this. Lactose intolerance, or tolerance, is another example. If you look at individuals in certain parts of Africa, who transitioned from hunting into more agrarian cultures, they’ve been able to adapt to digest milk. So it’s an adaptive characteristic. It might seem mundane, but it’s an example of how our genomes have evolved.
SSF: Are there things in X-Men that you found particularly ludicrous or compelling?
CE: Obviously, the amount of mutations that they must have in the number of genes is awe-inspiring. But it’s fun to think about. I think it paints mutations in an interesting way, and it makes mutations not such a bad thing, because who wouldn’t want to be able to read people’s minds, or take on any form?
SSF: And if you think about people living in icy terrain for centuries, maybe it’s not that far-fetched for them to have a genetic mutation that helps them, not exactly turn into a fireball, but better withstand cold?
CE: Most certainly. I think it brings up all kinds of fascinating possibilities. When we think of sickle cell traits, it’s pretty amazing that people who carry the trait who came from individuals who lived in areas where malaria was a problem now have this protective mechanism. If mosquitos were rampant with malaria in the U.S, those individuals would be far more resilient. But when you’re outside of that environment, it creates complications.
SSF: What do you think of the idea in the film that the mutants are more evolved than “regular” humans and are built to outlast us?
CE: It’s really difficult for many of us to think in terms of evolutionary time, because we’re talking millions of years. There’s a fascinating interactive art exhibit at the National Museum of Natural History in D.C., which asks users to think about adaptation, and what humans will look like in the future. For instance, if the planet becomes covered with water, will individuals with webbed feet and hands, have some kind of selective advantage? I often ponder, living in the environment that we live in, with the air quality being worse and with global warming, are there characteristics that people will acquire to be better equipped with the changing Earth? Personally, one of my major concerns is that our evolution moves much slower than our surroundings. One example is our change in diet: We have changed our diet so much, and our need to store fat is not nearly as important as it was thousands of years, but our evolution hasn’t caught up with the environment that we live in.