Bro Sam Peter/ Azumah Nelson. Son of Yusuf. When man walks the world trembles. Uno why? He likes his necks.
I'd put Steve Cunningham, Mike Weaver, Carl Thompson and maybe Johnny Nelson over Ken Norton when it comes the the physique department.
I still don't see how we can tell whether someone has "freak" genetics, aside from extreme outliers (especially pre-steroids) who have physically obvious abnormalities. Primo Carnera, maybe Abe Simon, Valuev. Plus maybe Liston's abnormal arm length. For the rest, they might have just been better trained and generally talented. You can't easily parse out nature and nurture in boxing. Look at the disparate fates of many boxing twins.
I'll go with this one. Absolute genetic freak to be that tall for weight class with a +5 ape factor, yet be absolute top tier for weight class in terms of power and speed. Even more of a freak than plenty of others mentioned here. I'll also add a bit of a troll honorable mention here. Tyson Fury (the one of the 2nd Wilder fight). How a big guy can move like that and have great stamina, WHILE carrying what's probably 30-40lbs of excess fat, it also freaky. Imagine his speed and mobility if he had slimmed down to 10% BF.
All these guys were blessed in one way or another when it comes to genetics whether it was physique, natural ability or keeping there senses intact after years of punishment: Muhammad Ali Mike Tyson Julian Jackson Steve Cunningham George Foreman Earnie Shavers Carl Thompson Timothy Bradley Roberto Duran Archie Moore Max Schmeling Tex Cobb Oliver McCall Floyd Mayweather Klitschko Brothers Ruslan Provodnikov Bernard Hopkins Roy Jones Jr Jimmy Wilde Tyson Fury Deontay Wilder Anthony Joshua Jake LaMotta Sam Langford Manny Pacquiao Harry Greb Len Wickwar Marion Wilson
That genetic predisposition to be susceptible to steroid addiction served him well. Talk about making lemonade out of lemons...
Rocky Marciano, with his dense bones. That made him naturally tougher and stronger than he should have been for his size.
And the thing with Fury is that, as is, he might be in a very uncommonly fine yet optimal balance - which is to say, if he ain’t broke, don’t fix him. I don’t know that we can necessarily project him to be better by satisfying certain numbers (viz body fat) and physical appearances that lend to “our” idea of improved fitness and effective quality. In essence, given what Fury does, as is, is truly freaky.
*cracks fingers* member 2041 being a high responder to steroids actually IS a genetic predisposition and the mileage varies between everybody that’s why there are countless guys in the bodybuilding circuit blasting everything who will never be Ronnie Coleman. Sometimes the best sprinters, athletes ect just have the best response to gear.