The problem with this is that people like this then tend to train and go on to do phenomenally well with extreme ease. In the physical domain, Mike Tyson is a good example. He was 'discovered' by a detention counselor when he was 13. 2 years later he would be the junior olympic world champion for two years in a row. Then he went professional and won his first 19 fights by knockout, 12 in the first round. He then went around and won every world championship belt there was - getting his first world championship title 8 months before he was old enough to legally buy a beer.

For the mental realm you have people like Srinivasa Ramanujan [1]. He had next to no formal training in mathematics yet would contribute immensely to a wide array of mathematical fields before the end of his brief life, dying at 32.