A short and sweet post today. I will preface this post by reminding my readers that I am notoriously skeptical of all genetics studies, not just this one. So take my opinions with a grain of salt, for they are only opinions.
Sigh
At the end of my work week, the last CNN headline I want to see is anything related to “sequenced Hitler’s DNA.” Recently, some famous geneticists and historians collaborated to sequence Hitler’s genome from a bloodstained piece of fabric recovered in 1945.
It used to be very, very expensive and time consuming to sequence human DNA. It took roughly 13 years and an estimated $3 billion to sequence the first human genome in the early 2000s as part of the Human Genome Project. We have better sequencing tools available now, and some cost estimates sit at just a few hundred dollars for one human genome.
But here’s what you need to know so we can talk some (educated, evidence-based) trash.
Sequencing is Not Objective
Sequencing DNA does not reveal objective truths. The researcher in charge of sequencing data makes many assumptions and subjective decisions about how to interpret, clean, and manage the data. The news tends to view sequencing as a foolproof, impartial method, but if you learn anything from this blog, let it be that sequencing is not objective. There are ways to make it more rigorous, but just like all science, we are not dealing in truths.
In fact, to combat bias, scientists are expected to make their data analysis methods and raw data publicly available, and their data can be subject to audits by the funding agency at any time. There are extensive databases where sequences are uploaded and can be annotated by scientists at other institutions to ensure the conclusions we make from DNA sequences are verifiable across universities and research centers.
There’s No Preprint
In the publishing world, it’s becoming more and more common to make your papers available as “preprints.” Preprint articles, managed by journals like bioRxiv (pronounced “bio-archive”), are publication drafts that are released before a paper has completed the peer-review process.
Why does it matter if someone publishes a preprint? Preprinting allows more people to critically review the work, even if they are not the official reviewers that will approve or reject the paper for publication. There’s always the caveat that the preprint article may not be the same as the final version of the publication, but the main body of the work will be mostly unchanged. There are a handful of reasons you may elect not to publish an article as a preprint:
You cannot afford to wait longer for the peer-review process to finish
It is too difficult to adapt your publication draft to a journal’s preprint policies.
You are afraid someone will copy your study and publish it before your paper has made it through the peer review process.
Now, if I was the one sequencing Hitler’s DNA and claiming he was higher genetic risk for stigmatized mental health disorders and delayed puberty, these issues would not apply to me. The authors of this study are very high profile geneticists and have historically been involved in genetic identification of major historical figures. They can afford to submit to preprint and delay the process by a few months. They are experienced with the publishing world, they have surely submitted other articles for preprint.
And lastly, they are the only ones in the world with access to Hitler’s DNA. Nobody can copy their study and publish it before they do.
The Study is Untargeted
The main research questions motivating this study are unclear to me, and in my opinion, it’s unlikely they had a targeted hypothesis. Their test subject is one of the most famous, well-documented, and hated figures in human history. If it were me, it would be easy to take a more untargeted approach to get some media attention on an already controversial topic. In other words, this is a “see where the data takes you” study, rather than a “we designed the study to test one specific prediction.”
Not all untargeted research studies are poor ones. Some of the most important scientific discoveries have been “accidents.” CRISPR gene editing technology interestingly had roots in the dairy industry. Post-it notes were a complete accident. Potato chips. The list goes on.
So why don’t I like this study?
There is No Good Research Outcome
Hitler’s life is one of the most well-documented in history. He was constantly, constantly surrounded by people who wrote down his mannerisms, decisions, emotions, favorite meals, whether he tied his left or right shoe first. It wasn’t like he was trying to keep anything secret (see Mein Kampf). What new information about his life is his DNA going to contribute?
An obvious counterargument is understanding his genomics may clarify why he was the way he was: irritable, arrogant, full of hatred, and yet a compelling, decisive leader. So, maybe his genes could reveal distinct differences from the average, non-hateful person to explain these traits.
This is an exciting idea for a certain subset of the population, except we must remember that Hitler was a person just like the rest of us. The study found genetic indicators for autism, ADHD, and schizophrenia. There have been millions of people over human history with these disorders that have not had violent tendencies. A well-trained scientist would refrain from saying this finding may indicate his personality and violent tendencies could be driven by these genetic differences. But the media will not refrain from making this conclusion.
The study further proposes Hitler may have had a condition known as Kallmann syndrome, which can prevent or significantly influence puberty. I wish I was kidding, but the main author of the study was careless enough to admit to the reporter that some patients with Kallmann syndrome have a micropenis. Though, Hitler was known to have some genital irregularities that may overlap with symptoms of Kallmann syndrome.
My main point here is the authors have not exercised any restraint in discussing the implications of their study. If you tell a reporter that you think Hitler could be genetically at risk for Kallmann syndrome, they will take away that Hitler had Kallmann syndrome. And if you tell them that it’s possible to have a micropenis and have Kallmann syndrome, they will take away that Hitler had a micropenis.
If the authors didn’t discover anything significant in Hitler’s DNA, the best case scenario would be once again confirming that Hitler was a terrible person.
I don’t have a familial connection to this wretched part of human history, but if I did, I would be enraged at the idea that someone even think of proposing a genetic excuse for Hitler’s behavior. It is not worth our time to rationalize on a biological level why he acted the way he did. There is no good outcome to this research, even if the main authors may think the findings are significant.
There’s not much else to discuss about this study until the findings are officially published. And if there’s something new to say about it, we’ll revisit the findings.
The point about sequencing not being objetive really resonates. Too often we see genetic studies presented as if they reveal unchangeable truths, when in reality there are so many subjctive decisions in data interpretation. The lack of a preprint here is particularly telling given the profile of the researchers involved. It makes you wonder if they're trying to control the narrative before opening it up to broader critique from the scientific comunity.