Is there any animal, closely related to humans that a human can breed with?
Ok, I am not supporting bestiality here. But, I just came to know about a Dogxim, a dog fox hybrid and I had known for a long time that horses and donkeys can breed (to produce a mule). So, I was just curious, can humans breed with any other animals closely related to us?
No, not since Neanderthals, Denisovians and friends went extinct.
Even Neanderthals are a bit of a partial case, since the hybrid males were mostly sterile. We know this from the pattern that Neanderthal genes appear in modern DNA.
Most people of non-African origin (a fact that helped pinpoint where the mixing happened and when) have 1-3% or so, the amount varying by person and region.
Uhh, I think there was a Nature article about it. Per the Wikipedia, basically there's just stretches of the X chromosome that are deserts of Neanderthal DNA, because when a Neanderthal allele is present and there isn't a second copy, it's a reproductive dead end and selected out.