Green is not the only person to wonder if there is a genetic connection to the Blue Fugates.
Jennifer L. Adams Horsley of Hartford, Ind., said she is certain that her mother-in-law, Amanda Susan Parker Horsley, was descended from the family.
"She was from the upper regions of Kentucky," she said. "Her lips and nail beds were perpetually blue."
"They were like that almost all the time," said Horsley, 62, and a retired nurse. "The color depended on when she got upset or was cold. It was so pronounced that everybody thought she was sick."
Parker died at 73 of liver cancer nine years ago, "So we may never know," said her daughter-in-law.
The family presumes that Parker's mother, Mary McCleese Parker, also had the condition.
"My grandmother was blue," said Horsley's husband John H. Horsley. "Everyone thought it was real odd."
He grew up in Ohio, but his parents had met in Carter County, Kentucky. The Horsleys said they know of no other children or grandchildren who inherited the gene for methemoglobinemia.
"It was never diagnosed and doctors were baffled," said Jennifer Horsley. "I don't think they had even heard the name."
Methemoglobinemia may be passed down through families or can be caused by exposure to certain drugs, chemicals or foods.
In Green's case, the disorder was genetic and occurs when there is a problem with the enzyme called cytochrome b5 reductase.
In type one, the red blood cells lack the enzyme. In type 2 -- also called hemoglobin M disease -- the enzyme doesn't work anywhere in the body.
Green has M disease, which is caused by defects in the hemoglobin molecule itself and can be passed down from only one parent.
The disorder once saved his father's life, according to a story told by Green's mother. "A woman shot him five times and he didn't bleed out because his blood was so thick."
For that very reason, Green takes three different blood-thinning drugs to prevent blood clots and morphine for the pain.
"I have found a way to live around it the best I can," he said. "It's caused me a lot of emotional problems.
As for finding his father, "I would really like to more about how he grew up with it and how he dealt with it. My father and I never met, but come to find out, we are a lot alike."