The "Blue Fugates" were a family in Troublesome Creek, Kentucky, with a rare genetic condition—methemoglobinemia—caused by a deficiency of cytochrome b5 reductase, turning their skin blue.
The trait originated with Martin Fugate (born 1820), who had four blue-skinned children. The condition persisted through generations but faded due to intermarriage with non-carriers. No living blue Fugates are known today, but the case remains a fascinating chapter in medical genetics.