Groundbreaking DNA analysis of Adolf Hitler's blood has uncovered some extraordinary findings about the dictator's ancestry and possible health conditions.
Painstaking scientific testing by a team of international experts has been able to debunk a rumour on whether Hitler had Jewish ancestry (he didn't) and determine that he had a genetic disorder which affects the development of sexual organs - all from an old blood-stained swatch of fabric.
While clickbait headlines have focused on whether the Nazi dictator had a micropenis and only one testicle, more serious are the findings that his DNA showed very high scores - in the top 1% - for a predisposition to autism, schizophrenia and bipolar disorder.
Does this mean he had these neurological conditions? Absolutely not, say the experts - it's not a diagnosis.
But nevertheless, concerns have been raised about stigmatisation and how ethical the research was, prompting the question - should it have been done at all?
I agonised over it, says Prof Turi King, within the first few minutes of Saturday's Channel 4 documentary on the research, Hitler's DNA: Blueprint of a Dictator.
The genetics expert told the BBC that when she was first approached to take part in the project several years ago, she was very aware of the potential implications on studying the DNA of someone like Adolf Hitler - I'm not interested in sensationalising things.
But, she says, it was likely to be done by someone at some point, and at least under her watch she could ensure the research was done with academic rigour and with all the caveats and guardrails in place.
Prof King is no stranger to high-profile and sensitive projects - she led the genetic investigation to establish the identity of Richard III's skeleton after it was discovered buried under a car park in Leicester in 2012.
The bloodied swatch of fabric - now 80 years old - was cut out of the sofa in Hitler's underground bunker, where he killed himself when Allied forces descended on Berlin at the end of World War Two.
While inspecting the bunker, Colonel Roswell P Rosengren of the US army saw an opportunity to get a unique war trophy and pocketed the fabric. It's now framed and on display at the Gettysburg Museum of History in the US.
The scientists are confident it really is Hitler's blood, as they were able to perfectly match the Y-chromosome with a DNA sample from a male relative that had been collected a decade prior.
The results, which are now under peer review, are indeed fascinating.
It is the first time Hitler's DNA has been identified, and over the course of four years, scientists were able to sequence it to see the genetic makeup of one of the world's most horrific tyrants.
What is certain, experts say, is that Hitler did not have Jewish ancestry - a rumour that had been circulating since the 1920s.
Another key finding is that he had Kallmann syndrome, a genetic disorder that, among other things, can affect puberty and the development of sexual organs. This can also affect libido, which is particularly interesting, said historian and Potsdam University lecturer Dr Alex Kay, who is featured in the documentary.
More complicated and controversial are the results suggesting Hitler may have had one or more neurodiverse or mental health conditions. Looking at his genome, and comparing it with polygenic scores, they found that Hitler had a high predisposition for autism, ADHD, schizophrenia and bipolar disorder.
But some genetic scientists have raised concerns that the findings are an oversimplification.
The UK's National Autistic Society was quick to respond, calling the findings a cheap stunt. Autistic people deserve better than this, said Tim Nicholls, assistant director of research.
The BBC put the concerns to Channel 4 and Blink Films, the production company that made the documentary. In a statement, it pointed out the programme emphasises that the genetic insights revealed in the films shed light on Hitler, but they don't tell us he was biologically predestined to behave in a particular way.
So should this research have been conducted at all? The BBC spoke to a range of genetic scientists and historians, and the answer depends on who you ask. Those in the documentary, believe it helps to build a more rounded profile of Hitler.
We should do whatever we can to understand past extremism, says Prof Weber. Others are more skeptical, fearing that DNA research might not yield the contextual insights necessary to explain complex historical figures.
As research awaits publication, experts stress the necessity of careful and responsible communication regarding its implications.
