Because I write nonfiction, I love to read fiction. But I avoid crime novels, especially about serial killers who carry out gruesome rituals on innocent young women. When a book publicist sent me info about a new book, “The Ripper Gene,” however, I couldn’t resist. The book is published by Forge, Tom Doherty Associates, which is part of Macmillan.
Written by Michael Ransom – known in biotech circles as molecular pharmacologist Michael Burczynski, PhD – The Ripper Gene is a cleverly-crafted, tightly unfolding thriller based on solid science. And that’s why it’s scary.
The Ripper Gene is a case study in genetic determinism, the idea that our DNA dictates who we are and how we behave. The protagonist, neuroscientist and FBI profiler Lucas Madden, has discovered a “damnation algorithm” genotype that predisposes those who have two copies of it to violence.
Early in the book, Madden/Ransom takes pains to explain that the damnation algorithm is more complicated than a lone serial killer gene, in jargon and then in plain English:
“Importantly, we don’t just look at single nucleotide polymorphisms, as scientists did in the past. We can now investigate many different aspects of human DNA – its methylation patterns, microRNA binding sites, copy number variants, insertions and deletions, just to name a few. When we examined the totality of genetic differences that can be observed, we found that key differences between violent offenders mapped to several dozen human genes … all of which are linked in one way or another to neurochemical signaling in the brain.”
But the focus indeed becomes a single gene, “ripper,” that encodes a subunit of a dopamine receptor, expressed in the amygdala. It’s a plausible set-up for the biology of violence.
We had a preview of the risks of attributing violent behavior to genetic information half a century ago. In 1961, a tall, healthy man, known for his boisterous behavior, had his chromosomes checked after fathering a child with Down syndrome. The man had an extra Y chromosome. Could that have caused his aggression?
A few other cases of aggressive men with extra Y’s were reported. Then in 1965, British geneticist Patricia Jacobs surveyed 197 inmates at a high-security prison in Scotland. Of twelve men with unusual chromosomes, seven had an extra Y. After Jacobs’s findings were repeated for mental institutions, Newsweek ran a cover story on “congenital criminals.” An extra Y became a legal defense for committing a violent crime, a connection that eventually became a plot on Law and Order and other programs.
In the early 1970s, newborn screens began in hospital nurseries in England, Canada, Denmark, and Boston, with social workers and psychologists visiting parents of XYY boys to offer “anticipatory guidance” for dealing with their toddling future criminals. By 1974, geneticists and others halted the program, recognizing that the well-meant intervention could invite a self-fulfilling prophecy.
In fact, 96 percent of the one in a thousand males with an extra Y can blame their extra chromosome for only great height, acne, and learning disabilities. But might the large size of such boys lead teachers, employers, parents, or others to expect more of them, because they appear older, especially given the learning disabilities? Might that stress of expectation provoke some individuals with an extra Y to respond with aggression?
XYY syndrome continues to be a harbinger of what may happen when we all know our genome sequences. At Bioethics Today I addressed a 2012 study by criminologists reawakening the “blame the extra Y” theme: “These simple conclusions based on fuzzy data from non-geneticists feed the genetic determinism mindset that we are our genes. And that can lead to making excuses for antisocial behavior, or losing hope of changing it, for if a trait is encoded in our DNA sequences, then we can’t control it.”
That’s eerily like what Lucas Madden says when confronting the killer at the end of The Ripper Gene: “You kill because you think you have the right to kill. And it’s a conscious decision on your part. Your genetics had precious little to do with it, you piece of shit.”
A second historic example of blaming genes is the monoamine oxidase A (MAOA) gene, aka the “psycho” or “warrior” gene. The association of certain variants of this gene with violent behavior dates to a study of a Dutch family published in 1993, with 13 males who had “X-linked borderline mental retardation with prominent behavioral disturbance.”
The family members who had committed arson, attempted rape, and engaged in exhibitionism shared a mutation in a gene on the X chromosome that encodes MAOA, the enzyme that oversees metabolism of the neurotransmitters dopamine, serotonin, and norepinephrine. Like the XYY scenario, the MAOA-violence connection spread beyond the genetics community. An attorney used the “MAOA deficiency defense’ to attempt to free a client from impending execution for murder, and an appeals court in Italy reduced a convicted killer’s sentence by a year because of his MAOA status. A talk-show host joked that people with the “mean gene” should be sterilized.
Online Mendelian Inheritance in Man, my favorite source for all things human genetics, is more polite. It lists “susceptibility to antisocial behavior following childhood maltreatment” for men with certain variants of the MAOA gene.
Exploring Mutations in Fiction
The idea for The Ripper Gene grew out of a grizzly memory from the author’s adolescence, spun into a serial killer thriller with at least four possible characters who could’ve done it. As the plot unfolds, the dopamine receptor subunit gene itself becomes a powerful clue, and its recessive nature part of an eloquent metaphor. Each victim holds an apple that hides an embedded razor blade, like people fear will be handed out to children on Halloween. But it’s also an eerie symbol of the hidden nature of a recessive gene.
I don’t want to spill any spoilers. But the ultimate message of the novel is not so much the degree to which inheriting a genotype that affects a neurotransmitter receptor increases the likelihood of criminal behavior, but more about discrimination based on knowing an individual’s genotype.
Oddly, as soon as I finished reading The Ripper Gene, I picked up Summer Secrets, by Jane Green, a futile attempt to delay the coming of autumn. I was surprised to discover that it’s about a woman coming to terms with her alcoholism when she discovers that the man she thought was her father really wasn’t – and her real dad suffered from alcoholism too.
I’m glad that the idea of genetic determinism has filtered into crime novels and summer beach reads. It means that the general reading public is already thinking about what may happen once sequencing our genomes becomes routine, albeit one gene per plotline. Peter Donnelly, director of the Wellcome Trust Centre for Human Genetics, recently wrote in
PLOS Biology: “Within 15 years, there may be one billion humans whose genomes have been sequenced, in many cases with links to electronic health data.”
Will we use any of that information to excuse deviant behavior? The Ripper Gene provides a compelling look ahead.
(The description of XYY syndrome and MAOA are from my textbook, Human Genetics: Concepts and Applications, McGraw-Hill Education)