The blue people of Kentucky, widely known as descendants of Martin Fugate, who settled near Hazard, Kentucky, have baffled science for almost 150 years, but no more. On Thursday, ABC reported that modern science has solved the mystery of Blue Fugates, Dr. Cawein discovered that "The Blue People of Troublesome Creek," as researchers referred to them, had a genetic condition called methemoglobinemia, a blood disorder that results in blue-tinged skin.

Martin Fugate came to Troublesome Creek from France in 1820, and family lore says he was blue. He and his wife, Elizabeth Smith, bore seven children. Four of the children were blue. Troublesome Creek was isolated from the outside world, with no railroads and few roads to bring in outsiders. The Fugates married cousins and neighbors, keeping their blue genes within the bloodlines.

Methemoglobinemia is a blood disorder in which an abnormal amount of methemoglobin, a form of hemoglobin, is produced, according to the National Institutes for Health. In methemoglobinemia, the hemoglobin is unable to carry oxygen and it also makes it difficult for unaffected hemoglobin to release oxygen effectively to body tissues. This results in a blue or purple tint to a patient's lips and skin, while the blood appears to be the color of chocolate.

"It's a fascinating story," said Dr. Ayalew Tefferi, a hematologist from the Mayo Clinic, "It exemplifies the intersection between disease and society, and the danger of misinformation and stigmatization."

The blue skinned family of Kentucky was documented in "Blue People of Troublesome Creek" published in 1982 by Indiana University's Cathy Trost. According to Trost's detailed account of the family, Benjy Stacy lost his blue tint within a few weeks of birth, but his fingernails and lips still turned blue when he would get cold or angry.

One of Martin and Elizabeth Fugate's blue sons, Zachariah, married his mother's sister. One of their sons married a Ritchie girl and had eight children. One of them was Luna, Benjy's grandmother. Luna married John Stacy and they had 13 children.

The blue skinned family of Kentucky may have a unique disease that has caused embarrassment and stigma for their family, but it's likely they won't be passing it along to anyone outside of Hazard County.