In the Appalachian Mountains rests a medical oddity so unusual that it at first seems a massive hoax. Dating back to the early 1800s, an isolated family in eastern Kentucky ― who can trace their roots back to a French orphan ― started producing children who were blue, according to the British Daily Mail newspaper Thursday.

As a result of a coincidental meeting of recessive genes, intermarriage and inbreeding, members of the Fugate family were born with a rare condition that made them visibly discolored. The mystery behind the astonishing picture of the Fugates, which has been baffling people for years, appears to have finally been solved, the report said.

It began when Martin Fugate, a French orphan, settled on the banks of eastern Kentucky's Troublesome Creek to claim a land grant in the early 19th century.

He married a red-haired American named Elizabeth Smith ― who had a very pale complexion ― and their union formed a genetic mutation that resulted in their descendants being born with blue skin.

Looking at the portrait, they appear to have been either Photoshopped or made up to mimic characters from children's cartoon The Smurfs, but science proves that the condition is in fact real, the report said.

Called methaemoglobinaemia (commonly known as met-H), the condition reduces the individual’s ability to carry oxygen in their blood. As a result, their blood is darker than the color typically found running through people’s veins.

Because the Fugate family lived in such an isolated part of the Kentucky, they intermarried with a neighboring family for generations which led to a relatively “pure” gene pool where the met-H gene appeared much more frequently, the Daily Mail said.