Mythomania

They want your blood. The beasts of our unruly imaginations, the vampires and werewolves of our gothic past, they want that vital stuff that drives you. The myths have existed for centuries, these dark companions of humanity. Our shadow siblings have survived ages in the comfortable dark, serving as the stuff of nightmares for all of us who have ever started at an unknown shape in the night. These creatures represent our collective fear of the black, the unknown. But these creatures, oddly enough, are based on reality. In fact, they are based on biochemistry.

It all comes down to the blood. Uroporphyrinogen decarboxylase, a simple (well, not so simple) enzyme, designed to help break down you assemble your hemoglobin. Hemoglobin, of course, is the wonderful material that serves your blood so ably as a sherpa of oxygen. Oxygen, however, is the hazardous trade of biochemistry. We need it to drive the reactors that keep our cells flush with energy, but like any source of energy, it comes with risks. As a substance, it loves to attack us for our electrons, to damage the infinitely delicate material that makes up cells and DNA, our molecular identity. To tame this unruly resource we have harnessed equally dangerous materials, locking reactive intermediates into a closed ring, our own tamed beast: hemoglobin.

Each stage of hemoglobin assembly has an intermediate flush with potential destructive capability. It is this chain of manufacture, this biochemical supply line, that gives us our favorite myths. The vampire involves a form of porphyria (a breakdown in the enzymes for hemoglobin assembly) in which a byproduct forms that is extremely reactive to sunshine. This leads to someone who is constantly anemic (and thus hungry for the salty iron of blood), and prone to immediate and dramatic burns upon exposure to sunlight.

The werewolf suffers from hypertrichosis, hair growing from every surface. These poor individuals might suffer from a slightly different porphyria, that of cutanea tarda. They also burn, but the more dramatic side effect of failed synthesis is an overgrown thatch of hair. everywhere.

These deep dark myths, these reflections of the lost soul of humanity, are merely the deranged impressions the sick leave on the uninformed. This extends to our other monsters in human form, the zombie (most likely suffering from hansen's leprosy), the cyclops (holoprosencephaly), and the mermaid (sirenomelia).

Funny how understanding makes it less mysterious, but more disturbing. These creatures aren't the stuff of legend. They are the sad reality of disease.