Researchers say they have verified and sequenced Hitler’s DNA. A new documentary reveals the findings

Researchers have analyzed a DNA sample believed to belong to Adolf Hitler, revealing that the dictator of Nazi Germany had a genetic marker for a rare disease that could delay puberty, according to a new documentary.

The research, which lasted more than four years, was led by geneticist Turi King, a professor at the University of Bath in the United Kingdom, known for identifying the remains of King Richard III. King said she verified that a piece of cloth taken from a couch in the bunker where Hitler committed suicide in 1945 was soaked in the dictator’s blood by comparing a DNA sample recovered from the blood with that of a confirmed relative of Hitler’s.

In addition to suggesting the possibility that Hitler suffered from a hormone-disrupting congenital condition called Kallmann syndrome, the documentary examined rumors that the dictator had Jewish ancestry and investigated whether he had a genetic predisposition to certain mental health problems. Titled “Hitler’s DNA: A Dictator’s Plan,” the documentary will be broadcast on Channel 4 in the United Kingdom on Saturday.

However, the results shared in the documentary have not been reviewed by other scientists in the field or published in a scientific journal, making it difficult for experts not involved in the project to assess the validity of its claims. King said the analysis had been submitted to a “top tier” journal and said she hoped the work would be published soon.

The small piece of frayed fabric began its journey in 1945 in the hands of US Army Colonel Roswell P. Rosengren, who served as communications officer to General Dwight D Eisenhower. When Rosengren was allowed into Hitler’s bunker by Soviet forces, he cut a piece of fabric from a blood-stained sofa, according to the documentary. The sample remained in the Rosengren family before being put up for auction in 2014 and purchased by the Gettysburg Historical Museum in Pennsylvania.

“We didn’t know what we were going to find,” King said. “This could have been the most boring genome on the planet, but it was amazing.”

The most striking finding in the team’s analysis was that Hitler had a mutation in a gene called PROK2. Variants in this gene cause Kallmann syndrome and congenital hypogonadotropic hypogonadism, King said. In boys, these conditions can delay puberty and cause the testicles to not descent.

“Basically, they are characterized by low testosterone levels. You either don’t reach puberty or you go through partial puberty…5 percent of cases are associated with a micropenis,” King said, referring to a small but normally structured penis.

Clues in the historical archives

At the time of his death, Hitler was observed at the end of the couch with a gun and blood splattered on the couch and wall behind him, said Nicholas F. Bellantoni, archaeologist emeritus at the Connecticut State Museum of Natural History. He examined parts of the sofa, which is now in Russia, in 2009.

“If it is confirmed that the provenance of the sofa material used came from the bunker and the sofa on which Hitler and Eva Braun died, then the probability that the blood came from Hitler is very good,” Bellantoni said by email.

The new details put forward by King appear to match the historical record, according to Alex Kay, an expert on Nazi Germany and lecturer at the Chair of War Studies at the German University of Potsdam. Kay also appeared in the documentary.

He noted that a medical document from Hitler’s time in prison after a failed coup known as the Munich Beer Hall Putsch in 1923 suggested the dictator suffered from right-sided cryptorchidism – a condition in which a testicle does not descend into the scrotum.

“The discovery of Kallmann syndrome is, for me personally, as a historian and as someone who has spent over 20 years researching the Nazis, a major discovery,” Kay said. He added that this information potentially explained Hitler’s lack of personal connections.

Kay and King said the findings also put to rest persistent rumors that Hitler had Jewish ancestry — speculation that stemmed from the fact that Hitler’s grandmother became pregnant while working in a Jewish home, according to the documentary.

Since the Y chromosome data analyzed in the research matched the DNA of Hitler’s male relative, King said it was not possible that Hitler had Jewish ancestry. “If that were the case, we wouldn’t have gotten a DNA match on him,” King said. “This DNA match not only confirmed that this is indeed Hitler’s DNA, but also confirms that this story of human Jewish ancestry via his father is simply not true.”

The value of historical DNA

King said she had some initial reservations about participating in the documentary, but decided to participate because she felt her expertise would ensure the analysis would be scientifically rigorous. “It’s not just a documentary but an academic article,” she said, adding that she had no publication date to offer.

Scientists have already used DNA to study well-known historical figures. Beethoven’s DNA, recovered from a strand of hair, revealed that the composer had health problems. Archaeologists also widely use ancient DNA from human remains.

However, without information about the quality of the genome, the raw data or how the analyzes were carried out, it is not possible to assess the claims made in the documentary, according to Pontus Skoglund, senior group leader of the Ancient Genomics Laboratory at the Francis Crick Institute in London.

“Taking a step back, the scientific value of a media campaign like this, weighed against the possible stigmatization of people with these real illnesses today, can also be questioned,” Skoglund said.

He added that the researchers could have shared the results with the scientific community on what is called a preprint server before formal peer review and publication in an established journal.

It’s plausible that historical DNA could be extracted from the piece of fabric, but there needs to be a good rationale for studying the DNA of historical figures and a defined set of questions, said Tom Booth, Skoglund’s colleague and a bioarchaeologist at the Francis Crick Institute.

“There are numerous historical records documenting Hitler’s behavior in public and private,” Booth said by email. “(He) is probably one of the most studied figures in history, so I think it’s hard to argue that the DNA evidence adds much in that regard.

“Even diagnosing Kallmann syndrome may not be as simple as the headlines suggest. There can be many variations in how it manifests physically, and while that’s a plausible explanation for his undescended testicle, it doesn’t justify the amount of ‘micropenis’ in my news feed.”

A “small, small puzzle piece”

The researchers also said they calculated a polygenic risk score, which involves looking at a person’s DNA to quantify disease risk. Their results suggest that Hitler had an increased genetic predisposition to schizophrenia, attention deficit hyperactivity disorder, and autism.

However, the polygenic risk score is a tool used today for research purposes: it is not a diagnosis and does not necessarily mean that Hitler suffered from these conditions, said Ditte Demontis, a professor of psychiatric genetics at Aarhus University in Denmark, who participated in the research and appears in the documentary.

“Currently, we are in a state where polygenic risk scores for psychiatric disorders are only used in the context of research,” Demontis emphasized. “We can say something at the group level but not at the individual level.”

Demontis compared Hitler’s polygenic risk score with those of 30,000 Danes and found that if Hitler were alive today, “his score for schizophrenia, autism, and bipolar disorder was actually higher than that of 99% of individuals in the Danish population.” It is also rare to have a high polygenic risk score for all three conditions, she added.

“This is not a diagnosis and I also want to emphasize that the score in no way leads to a certain type of behavior or action,” Demontis said.

The king accepted. “We have a lot of difficulty not stigmatizing people with these conditions, because, you know… it’s incredibly rare for people with these conditions to commit acts of violence,” she said.

“And the other thing is, Hitler didn’t act alone, he had hundreds and thousands of people helping him,” King noted. “They won’t all have the same genetic makeup as him. His genetics are just a very small piece of the puzzle.”

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