We should acknowledge the remarkable corroborating facts, here. One of the primary symptoms of Kallmann Syndrome is cryptorchidism. Radl's excellent article linked above includes this quote about a doctor in 1923 who diagnosed Hitler with cryptorchidism:
The records, taken during a medical exam following Hitler’s arrest over the failed Beer hall putsch in 1923, show that he suffered from “right-side cryptorchidism”, or an undescended right testicle.
Notes written by Dr Josef Steiner Brin, the medical officer at Landsberg prison, state “Adolf Hitler, artist, recently writer” was otherwise “healthy and strong”.
That was only one out of four doctors Radl cites, the other three of which did not note cryptorchidism, from which we can infer that Hitler's case, if it was real, could only have been a mild one. Nonetheless, it seems to be a quite rare disorder (
1 in 30,000), so the fact that a medical exam lines up with alleged genetic evidence is pretty good corroboration. Or if they're both fake it's a remarkable coincidence.
Something has to explain why Hitler's case was for the most part asymptomatic. Speculatively, it's possible that Kallman Syndrome is more common than believed but overlooked because it is asymptomatic. Also possible is that the syndrome was more common historically but less of an issue then because of higher testosterone levels, since it is well-known that male test levels have precipitously declined over time. A third possibility is that it was offset by his gigachad genes, as fireofice suggests above. Take your pick.
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It has to be taken separately that the media has sensationalized this story. They've made statements like Hitler "really did have only one ball" (The Telegraph) which is obviously false, "Hitler likely had a micropenis" (NY Post) which is statistically incompetent, and they're also trying to diagnose autism, bipolar, and schizophrenia which is obviously inappropriate from DNA sequencing alone. All of this is pretty standard for journalists, and they fully deserve all the derision for it, but it can be separated from what I presume to be more serious underlying work.
Notably, the same kind of thing happened back in 2010. When I look back at the original Dutch articles written about Jean-Paul Mulders, his statements were fairly tame and science-based. It was all the media reporting, especially in the English-language sphere, that took Mulders's work and claimed Hitler was actually a Jew or an African. Mulders was even responsible for debunking one Jewish story.
With the same research, Mulders was able to demonstrate that Alois Hitler, Adolf's father, was not a bastard but indeed a real Hitler. The story about Hitler's supposed Jewish grandfather, which had been circulating since the 1930s and had led to the most outrageous conspiracy theories, could thus also be relegated to the realm of fantasy.
translated from https://www.knack.be/magazine/de-zoon-v ... orgeprikt/
So I think it's best if we don't throw the baby out with the bathwater. The experts are not a problem so much as the journalists.