From real mermaids to the elephant man here are the weirdest human mutations. Subscribe to Science N 60 http://goo.gl/UvCbpX 6. Epidermodysplasia Verruciformis or the tree man illness is characterized by the formation of horn like structures on the skin and warts the take up an overwhelming amount of surface area on the body. The skin on the hands and feet becomes tough and thick turning a brown or yellow color resembling branches of a tree. Several types of HPV contribute towards this condition, but HPV 5 and HPV 8 are the ones that are most often associated with the mutation. Unfortunately, with tree man illness even when the warts are surgically removed that isn't a guarantee that they won't return. In the case of one man, Dede Koswara, who had 95 percent of his warts removed in 2008 only for them to resurface soon after. Even if one can't be completely cured, after several treatments the warts have been shown to at least grow back smaller each time. 5. Sirenomelia, the proper name for the better known Mermaid Syndrome, is the mutation that causes infants to be born with what looks like a mermaid tail. In the womb the legs start to rotate and are fused together due to only developing a single artery that cannot produce the blood flow needed to form the lower body completely. In the 19th century the afflicted fetuses were preserved in jars and displayed for people in 'freak shows' as mermaid children. It's an extremely rare condition and only affects 1 in 100,000 babies, but it is much more likely to occur in identical twins. Those born with Sirenomelia usually die within a few a days of being born and those who do survive don't live a very long life. 4. Progeria is the genetic mutation that causes accelerated aging in children. It's a rare condition caused by a mutation in the gene named LMNA. The children usually all display very similar characteristics, they lose body fat and hair. When they are born the babies look healthy and normal until around 18-24 months when the mutation starts to accelerate and becomes visible through their appearance. Sadly children with Progeria tend to die at an average age of 14 due to heart disease. 3. Not all mutations are visible on the outside nor are they all a hindrance to everyday life. The children of the Moken people, located off the coasts of Thailand and Myanmar, have developed the ability to see clearly underwater in depths up to 75 feet. The mutation of their eyes is actually the ability for the eye muscles to change the shape of the lens to increase light refraction, leading to underwater vision. This evolved ability allows them to scope out tiny brown clams deep underwater even while they look indistinguishable amongst the tiny brown rocks near them. Something that's hard for others to do even while wearing goggles. These sea-gypsies dominate the water! 2. Proteus syndrome or elephant man syndrome causes the overgrowth of body parts in a asymmetrical fashion. It varies from person to person and can affect any part of the body. At the age of 6-18 months the growths can start to occur and get more severe with age. Proteus syndrome can even cause neurological abnormalities that lead to seizures and vision loss, but also affect the person on an intellectual level. "The Elephant Man" a movie the brought to the light the real life man, Joseph Carey Merrick, who had Proteus syndrome and was a "freak" in the Victorian times. He was put on display for people to gawk at and weird theories as to why he was born the was he was started to bloom. One farfetched claim was that his mother was frightened by an elephant and that must be the reason. 1. Cyclopia is the birth defect whose name was inspired by the Cyclopes giants in Greek mythology. The condition causes a single eye that is located where the base of the nose usually takes its place. The nose can be absent or can be located above the eye in the form of a proboscis. Only one of the two eye sockets that we are normally born with forms which gives them their unique appearance. All of the causes leading to children being born with Cyclopia come from a unusually high presence of toxins in the body of the mother. The toxins in the body that cause the mutation could be from alcoholism, diabetes, and even from ingesting a toxic weed known as Corn Lily during pregnancy. Cyclopia is a fatal condition due to the underdeveloped facial features and other deformities to the heart and vital organs.