The Science of The X-Files: How Baby Peacock from "Home" Could Actually Exist
It's January, X-Files fans, which means we have less than a month to wait before our favorite alien conspiracy show returns for a six-episode miniseries. The pilot (which we saw at NYCC), airs on January 24th, but until then, we're going to give you daily articles about the fascinating science behind the X-Files, courtesy of science advisor Anne Simon and her book "The Real Science Behind the X-Files: Microbes, Meteorites, and Mutants."
We were extremely disappointed to find out that the upcoming episode of the X-Files revival called "Home Again" wouldn't be a sequel to the classic fourth season episode "Home," although not surprised, considering that Fox told the X-Files writers that the infamous Peacock clan could never appear on television again. But "Home" remains one of the most beloved (and controversial) episodes of the series, portraying a horrifying inbred mutant family with a horrifying inbred mutant baby that-plot twist- could technically exist in real life.
The episode begins with Mama Peacock giving birth to a horribly deformed and disfigured baby that is clearly not long for this world- so her sons bury it alive. Mulder and Scully are brought in once the body is discovered, and Scully diagnoses the child with not one, but four extremely rare genetic diseases. All of the diseases are real, two of them are, indeed, fatal to an infant, and there's nothing precluding them from being passed on to one child simultaneously (although it is, of course, highly unlikely). There are a couple of errors- Scully calls the diseases autosomal dominant when they are actually recessive, for example- but for the most part the science holds up.
Simon points out, however, that considering the rarity of these genetic diseases, it's unlikely that Scully would be able to diagnose them without the help of a specialist or a ton of research.
Or Scully's just a savant who knows everything. We'd accept that answer, too.
But the real kicker comes when Scully finds that Baby Peacock has some fairly out-there chromosomal abnormalities. Not only is there significant breakage, but the baby has two complete extra sets of chromosomes. I sort of assumed that this was speculative/pseudoscience, but as it turns out, it's not impossible. Babies are, in fact, born with an extra set of chromosomes in rare cases, and it's technically possible that a baby would be born with two, although considering that having one extra set of chromosomes is fatal, Simon terms it a "miracle" that the baby survived long enough to be buried alive.
There are two ways this could happen, which are suggested by Mulder and Scully, respectively. Scully suggests that there was an error in the cell division as the egg was forming, causing the egg to have three sets of chromosomes rather than two. If this egg were then fertilized by a sperm with an extra set of chromosomes, the fertilized egg would have four sets of chromosomes, just like Baby Peacock. Mulder suggests alternatively that the egg was fertilized by multiple sperm. As we all know, Mulder turns out to be correct, as Mama Peacock's egg was fertilized by at least two of her sons (yuck). But according to Simon, that would be the more likely explanation from a scientific perspective as well, as two-thirds of real-life instances of extra chromosome sets are the result of an egg being fertilized by multiple sperm. As a result, the combination of the extra chromosomes and the genetic diseases lead Mulder and Scully to the inbred mutant explanation.
Although the Peacock family is an extreme case that would probably never happen in real life (hopefully), Simon points out that "inbred human populations... are not an uncommon phenomenon." In the nineteenth century, a town called Chilmark in Martha's Vineyard was physically isolated from any other town by at least a half-day's trip, so the residents intermarried and brought out a genetic deafness that occurred in one quarter of the population. Every person in the town could communicate in sign language. To this day, several genetic diseases are more common within culturally isolated communities, such as Tay-Sachs in Ashkenazi Jews, dwarfism in the Amish, systemic sclerosis in the Chocktaw Indians of Oklahoma.
Also in this series:
The Science of The X-Files: Alien Acidic Blood and the Real-Life "Toxic Lady"