Unlike Griffins and Gargoyles and FP’s ability to become the sheriff of a town in which he once broke laws on the regular, the serial killer genes on Riverdale are real, in a sense. Betty tested positive for the genes herself, likely because of her father. Charles also revealed that he carries the genes, but that might prove to be a plot hole since it would mean their mother or his father, FP, also carries the gene. Or, it could be part of the mystery already surrounding Betty’s long lost brother.
The serial killer gene exists in real life.
The serial killer gene MAO-A, which is formally known as Monoamine oxidase A, is crucial to the regulating of behavioral function in the brain. Mutations in the gene, however, can result in aggressive and antisocial behavior, which is then associated with criminal activity. Studies have shown that individuals who have low activity MAO-A can exhibit higher aggressive behavior toward others, which is where it gained the nickname of serial killer gene.
Source : https://www.distractify.com/p/is-the-serial-killer-gene-real-riverdale