I really think almost every person has some degree of "abnormality/anomaly/defect/gift" - physically, physiologically, mentally - these can be caused by and can change due to genetics/age/illness/accident/experiences/environment.
The big question is - when does this become a problem for the person and the people around that person?
For example - I have arthritis in my hands and some of my fingers are crooked. Does this bother me? Yes - but not to the extent that it stops me from doing much of what I've always been doing. They look a little odd, but not enough so that most people will stare at them.
One of my cousins has such severe rheumatoid arthritis that her fingers were almost pointing 90 degrees from their "normal" position. She has had several surgeries to try to maintain as much use as possible of her hands.
I think this "range" is also possible with other conditions that humans are faced with.