Harvard geneticists believe humans and chimpanzees continued to interbreed long after the species split. Such interbreeding, or hybridization, puts evolutionary pressure on the X chromosome, causing it to change more rapidly than normal. The researchers found that the newest genes on the human genome appear on the X chromosome.
From this, researchers argue that ancestral humans continued to breed with chimps until 5.4 million years ago, when the split became permanent. This new view stands in sharp contrast to the consensus view that once speciation occurs, hybridization is “a negligible influence.” But according to Dr. David Reich of Harvard, the fact that hybridization has rarely been seen in other species “may simply be due to the fact that we have not been looking for it.”
The Harvard researchers caution that interbreeding of humans and chimpanzees is not possible in the present day. They point out that press reports of hybrid “humanzees” have invariably proven false.
CHAPTER 006
BioGen Research Inc.was housed in a titanium-skinned cube in an industrial park outside Westview Village in Southern California. Majestically situated above the traffic on the 101 Freeway, the cube had been the idea of BioGen’s president, Rick Diehl, who insisted on calling it a hexahedron. The cube looked impressive and high-tech while revealing absolutely nothing about what went on inside-which is exactly how Diehl wanted it.
In addition, BioGen maintained forty thousand square feet of nondescript shed space in an industrial park two miles away. It was there that the animal storage facilities were located, along with the more dangerous labs. Josh Winkler, an up-and-coming young researcher, picked up rubber gloves and a surgical mask from a shelf by the door to the animal quarters. His assistant, Tom Weller, was reading a news clipping taped to the wall.
“Let’s go, Tom,” Josh said.
“Diehl must be crapping in his pants,” Weller said, pointing to the article. “Have you read this?”
Josh turned to look. It was an article from the Wall Street Journaclass="underline"
A Genetic Basis for Controlling Other People?
TOULOUSE, FRANCE-A team of French biologists have isolated the gene that drives certain people to attempt to control others. Geneticists at the Biochemical Institute of Toulouse University, headed by Dr. Michel Narcejac-Boileau, announced the discovery at a press conference today. “The gene,” Dr. Narcejac-Boileau said, “is associated with social dominance and strong control over other people. We have isolated it in sports leaders, CEOs, and heads of state. We believe the gene is found in all dictators throughout history.”
Dr. Narcejac-Boileau explained that while the strong form of the gene produced dictators, the milder heterozygous form produced a “moderate, quasi-totalitarian urge” to tell other people how to run their lives, generally for their own good or for their own safety.
“Significantly, on psychological testing, individuals with the mild form will express the view that other people need their insights, and are unable to manage their own lives without their guidance. This form of the gene exists among politicians, policy advocates, religious fundamentalists, and celebrities. The belief complex is manifested by a strong feeling of certainty, coupled with a powerful sense of entitlement-and a carefully nurtured sense of resentment toward those who don’t listen to them.”
At the same time, he urged caution in interpreting the results. “Many people who are driven to control others merely want everybody to be the same as they are. They can’t tolerate difference.”
This explained the team’s paradoxical finding that individuals with the mild form of the gene were also the most tolerant of authoritarian environments with strict and invasive social rules. “Our study shows that the gene produces not only a bossy person, but also a person willing to be bossed. They have a distinct attraction to totalitarian states.” He noted that these people are especially responsive to fashions of all kinds, and suppress opinions and preferences not shared by their group.
Josh said, “‘Especially responsive to fashions’…Is this a joke?”
“No, they’re serious. It’s marketing,” Tom Weller said. “Today everything is marketing. Read the rest.”
Although the French team stopped short of claiming that the mild form of the master gene represented a genetic disease-an “addiction to belonging,” as Narcejac-Boileau phrased it-they nevertheless suggested that evolutionary pressures were moving the human race toward ever-greater conformity.
“Unbelievable,” Josh said. “These guys in Toulouse hold a press conference and the whole world runs their story about the ‘master gene’? Have they published in a journal anywhere?”
“Nope, they just held a press conference. No publication, and no mention of publication.”
“What’s next, the slave gene? Looks like crap to me,” Josh said. He glanced at his watch.
“You mean, we hope it’s crap.”
“Yeah, that’s what I mean. We hope it’s crap. Because it gets in the way of what BioGen’s announcing, that’s for sure.”
“You think Diehl will delay the announcement?” Tom Weller asked.
“Maybe. But Diehl doesn’t like waiting. And he’s been nervous ever since he got back from Vegas.”
Josh tugged on his rubber gloves, put on safety goggles and his paper face-mask, then picked up the six-inch-long compressed-air cylinder, and screwed on the vial of retrovirus. The whole apparatus was the size of a cigar tube. Next, he fitted a tiny plastic cone on top of that, pushing it in place with his thumb. “Grab your PDA.”
And they pushed through the swinging door, into the animal quarters.
The strong, slightly sweet odor of the rats was a familiar smell. There were five or six hundred rats here, all neatly labeled in cages stacked six feet high, on both sides of an aisle that ran down the center of the room.
“What’re we dosing today?” Tom Weller said.
Josh read off a string of numbers. Tom checked his PDA listing of numerical locations. They walked down the aisle until they found the cages with that day’s numbers. Five rats in five cages. The animals were white, plump, moving normally. “They look okay. This is the second dose?”
“Right.”
“Okay, boys,” Josh said. “Let’s be nice for Daddy.” He opened the first cage, and quickly grabbed the rat inside. He held the animal by the body, forefingers expertly gripping the neck, and quickly fitted the small plastic cone over the rat’s snout. The animal’s breath clouded the cone. A brief hiss as the virus was released; Josh held the mask in place for ten seconds, while the rat inhaled. Then he released the animal back into the cage.
“One down.”
Tom Weller tapped his stylus on the PDA, then moved to the next cage.
The retrovirus had been bioengineered to carry a gene known as ACMPD 3N7, one of the family of genes controlling aminocarboxymuconate paraldehyde decarboxylase. Within BioGen they called it the maturity gene. When activated, ACMPD 3N7 seemed to modify responses of the amygdala and cingulate gyrus in the brain. The result was an acceleration of maturational behavior-at least in rats. Infant female rats, for example, would show precursors of maternal behavior, such as rolling feces in their cages, far earlier than usual. And BioGen had preliminary evidence for the maturational gene action in rhesus monkeys, as well.
Interest in the gene centered on a potential link to neurodegenerative disease. One school of thought argued that neurodegenerative illnesses were a result of disruptions of maturational pathways in the brain.
If that were true-if ACMPD 3N7 were involved in, say, Alzheimer’s disease, or another form of senility-then the commercial value of the gene would be enormous.
Josh had moved on to the next cage and was holding the mask over the second rat when his cell phone went off. He gestured for Tom to pull it from his shirt pocket.