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Methemoglobinemia

A rare, recessive genetic disorder in which the body does not make the enzyme diaphorase.

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Diaphorase is responsible for converting methemoglobin into hemoglobin.
Hemoglobin carries oxygen in our bloodstream. Over time, it decays into methemoglobin.
Our bodies use diaphorase to speed up the reaction in which an electron donor gives up an electron to methemoglobin in order for the molecule to return to its hemoglobin state.

Iron (II) is found in hemoglobin. Over time the iron loses an electron, becoming Iron (III).

An electron is required to convert the iron back to Iron (II) to effectively transport oxygen.

In methemoglobinemia, the affected individuals are healthy because they still have enough hemoglobin to transport oxygen.
The only problem is, there is a build up of methemoglobin because they cannot convert it back into hemoglobin.
Methemoglobin is BLUE in appearance and shows through under the skin.

Martin Fugate’s Family�(and red headed bride)

Fugate Family Pedigree

�Luna Fugate and John Stacy

�Troublesome Creek�

Though this was a recessive disorder, and very rare, it continued showing up due to inbreeding.

Eleanor Fugate married Lorenzo Fugate.

Though Eleanor was not blue, she had blue brothers and a blue sister.

Lorenzo was blue and his nickname was “Blue Anze.”

They had the same last name at marriage and were first cousins.

There were no railroad tracks for a very long time, meaning no new people coming in to town.

Incompletely recessive

Carriers of the methemoglobinemia may exhibit features such as blue skin and fingernails (like Ben Stacy).
This suggests that they do not produce as much diaphorase as normal folks, but produce more than those with methemoglobinemia (two recessive alleles).

Virtually absent today

With the industrialization of the nation, many railroad tracks and roads were built.
Around the 1930’s people were able to easily migrate into Troublesome Creek, as well as leave and start new lives elsewhere.
Though the allele for methemoglobinemia has not decreased, the condition is not as prevalent as the odds of two carriers uniting is more rare than ever!
Today, methemoglobinemia is easily cured with ongoing treatment.

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