The Genetics of Vampires, Werewolves, and Giants (oh my!)

By Shannon Wieloch — October 26, 2017

2 min read

In the spirit of Halloween, we’re applying our genetics knowledge to some of the fabled haunts of the season. Did you know that genetic variants are at the heart of many of this season’s tales? Just like the saying, “There’s an app for that,” one could just as easily say “There’s a gene for that,” when referring to the origins of such Halloween legends as vampires, werewolves, and giants. Read on to understand what lies behind these folklores.

A Disease with Bite?

Tales of vampire-like creatures have existed for millennia and have been found in nearly every culture around the world, from India to Persia to Africa. Yet the folklore for the entity we know today as the vampire originates almost exclusively from early 18th-century southeastern Europe.

Beliefs on what caused one to become a vampire are as varied as the cultures from which they came; some believed that any corpse that was jumped over by an animal, particularly a dog or a cat, was feared to become one while others believed that vampires were witches or religious rebels while living. So what does the sound mind of science have to say about this myth?

Current thought is that the physical characteristics brought about by porphyrias, a group of blood disorders that can cause nerve or skin issues, may be what spurred the image of the modern day vampire. Erythropoietic protoporphyria (EPP) is the most common kind of porphyria to occur in childhood. Those with this condition have skin that is extremely sensitive to light. Prolonged exposure to sun can cause painful blisters, even from small amounts of sunlight that pass through a window. Due to the need to avoid sunlight, patients are often very pale and may only go outside during the night — adding further fuel to the legend of vampires.

Werewolf. . . Werewolf?!. . . There. . . What?. . . There Wolf. . . (There Castle.)

The legend of the werewolf is contemporary in comparison to vampires, developed between c. 1301 to c. 1800, and parallel to the belief in witches. In fact, werewolf trials, though marginal in comparison, were a thing at the same time, and in the same locations, as witch trials.

Per the literature, numerous physical characteristics would indicate a person was a werewolf, depending on the culture. There was the belief that if a child was born with hair, a birthmark or a caul on their head, they were supposed to possess shape-shifting abilities. Curved fingernails, low-set ears, and/or a uni-brow were other attributes linked to the legend. While all of these qualities have an underlying genetic component, there’s also a specific genetic syndrome related to this history.  

Hereditary hypertrichoses are a group of hair overgrowth syndromes that are extremely rare in humans. Ambras syndrome, which is just one condition in this group, is known historically as “werewolf syndrome”. Sources say that Ambras syndrome affects fewer than one in a billion people, and that only 50 cases have been described since the Middle Ages. In Ambras syndrome, vellus hair (the fine and light hair on most of the body, seen on the arms and faces of children) streams down the face and curls from the ears, flowing down the shoulders. Facial features are coarse, the nose long, and the face triangular. Teeth may be absent, fingers and nipples extra.

They Might be Giants?

There are giants in fairy tales, there are giants in the Old Testament, there are giants in the World Wrestling Federation (“Anybody want a peanut?”). They’ve been portrayed as intellectually challenged and violent to knowledgeable and kind. Could they all possibly stem from the same genetic variant?

The AIP genetic variant (R304*) identified in Northern Ireland can predispose an individual to acromegaly/gigantism. There is thought that this variant may be the source of Gaelic myths of giants in Ireland.

To quote Stephen King, “Fiction is the truth inside the lie.” While superstition and ignorance are at the heart of all myths, as you can see, these legendary characters aren’t any different from the rest of us. All of us have genetic variants. We just happen to know what some of theirs are.

So as you hand out tricks or treats to the parade of witches, mummies, and other classic characters this Halloween, perhaps you’ll wonder what other truths lie within fiction, waiting for science to uncover them.