Although Joseph Merrick's career in sideshows was rather short-lived, he became well-known by posterity for his affliction (he was known as the "Elephant Man") and the sweet nature that allowed him to befriend Queen Victoria. He only lived until 27 and spent years in the hospital due to his condition [source: Pednaud].
What that was is still a matter of some debate. Many claimed that Merrick must have had Neurofibromatosis Type 1 (NF1), where non-cancerous growths can take over parts of the skeletal or muscular system. But scientists are now leaning toward identifying the "Elephant Man" condition as Proteus Syndrome. In fact, an ethnographic study was conducted in 2011 to research why the media claimed NF1 was the cause of Merrick's physical differences [source: Legendre].
Proteus Syndrome is rarer than NF1, but it does have some of the same characteristics. It causes overgrowth of many parts of the body, including bones, tissues, skin and organs [source: Genetics Home Reference]. It also creates other health problems, including deep vein thrombosis.