1. Fibrodysplasia Ossificans Progressiva
Fibrodysplasia Ossificans Progressiva or also known as Stone Man Syndrome is a tissue disorder where there is a strange development of bone. Basically, someone’s soft tissues will become stiff, eventually making it impossible for the person to move.

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That wraps up our list of 10 most interesting and extremely rare genetic disorders. We hope you learned something new.