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.

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 discoloured.