A blind skateboarder from Michigan broke a Guinness World Record when he performed a 50-50 grind on a rail for a distance of 22 feet and 5 inches. Daniel Mancina, 35, of Royal Oak, said he took up skateboarding at the age of 13, the same year he was diagnosed with retinitis pigmentosa. The condition affects the light-sensitive layer of tissue in the back of the eye and often leads ...