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THE BAD SEED
Another evil government experiment is revealed in "Eve." According to Deep Throat, this experiment, conducted in the 1950s, created a series of identical boys and girls called the Adams and the Eves, with the goal of making superior soldiers. These children had extra copies of chromosomes #4, 5, 12, 16, and 22, which allegedly gave them heightened strength, intelligence, and, unintentionally, psychoses. Many of the Adams and Eves are either psychotic or homicidal. Could we create such super soldiers? First, let's examine our state of knowledge in the 1950s.
It was in 1953 that Drs. James Watson and Francis Crick published their famous paper describing the structure of DNA. In the '50s we also learned the number of chromosomes in the human genome was forty-six, with each somatic cell carrying two copies of each of twenty-three chromosomes. We learned the importance of the distinctive Y chromosome in sex determination. In 1958 we discovered that those with Down Syndrome have forty-seven chromosomes, with an extra copy of chromosome twenty-one, and so we learned the severe effects of trisomy, having three copies of a chromosome instead of two. It wasn't until the early 1960s that scientists sat down and gave each chromosome an official number. Around the same time, scientists identified other chromosomes which, when trisomic, caused various malformations. Scientists' ability to identify extra or rearranged chromosomes during this time was limited, though, causing confusion and uncertainty in results. It wasn't until 1970 that every individual chromosome could be identified for certain.
The only traits we had really connected to a specific chromosome were those associated with the X chromosome, since disorders associated with some of these genes would appear in men whose mothers did not display the disorder. Women have two X chromosomes, so they have two copies of the relevant gene, one of which could be healthy and the other not. If the healthy gene was dominant, the women would not express the disorder. Since men have only one X chromosome, if they inherited the unhealthy gene, then it would be expressed and they would have the disorder. One such X-linked disorder is red- green color blindness, from which Mulder suffers.
We're still working to discover which traits are associated with which chromosomes. Since our knowledge was so limited during the '50s, the idea that we could tell whether someone had three copies of chromosomes 4, 5, 12, 16, and 22 is extremely difficult to believe, let alone that we could purposely engineer someone to have this defect and then clone her. But might we be able to do such a thing today?
Now we know that trisomy is much more common than we ever thought, but that almost all cases result in the death of the fetus. Trisomic individuals who are born alive have multiple malformations, mental retardation, and a shortened life span. Dr. John Carey, professor of pediatrics at the University of Utah School of Medicine and Medical Advisor to the Support Organization for Trisomy 18, 13, and Related Disorders, says, "The reality is that they have an extremely difficult time." About 3% of pregnancies are documented to be trisomic, though the number is actually significantly higher, with most trisomic embryos miscarrying before the mother even knows she is pregnant. We discussed back in Chapter 1 how the process of meiosis, which creates the germ cells, can generate an egg or sperm with an extra chromosome. As women grow older, their chances of generating eggs with extra chromosomes increases. With women under twenty-five, trisomy occurs in one in fifty pregnancies. The number rises to one in ten with women aged thirty-six, and to four in ten with women aged forty-two. About half of all miscarriages and many common birth defects occur because the egg receives too many or too few chromosomes from the mother.
While trisomies can and do occur in any of the chromosomes, only a few generate fetuses viable enough to survive to birth. Aside from the X and Y sex chromosomes, the only trisomies that have allowed babies to survive for any length of time are for chromosomes 13, 18, 21, and 22. Ninety percent of those with trisomy 18 are miscarried or stillborn. Those few who aren't have only a 10% chance of surviving past their first birthday. Dr. Carey describes the infants. "Ninety percent have heart defects. They all have some degree of central nervous system involvement, so that fifty percent die in the first week. They aren't able to walk or to verbalize beyond the eighteen-month level. Most of them die because the brain doesn't give them the message to breathe."
As for the specific chromosomes mentioned on the show, extra copies of chromosome 16, as in the Adams and Eves, are even more common than those of twenty-one, famous for causing Down syndrome. Over one out of a hundred embryos has an extra copy of sixteen, which inevitably results in miscarriage. Dr. Carey stresses, "There has never been a live birth with trisomy 16." Similarly, trisomy 4, 5, and 12 have only been seen in miscarriages. The fact that the Adams and Eves have five trisomic chromosomes, or quintuplet trisomy, makes their chances for life infinitesimaly small. "There's no possibility," Dr. Carey says. So our Adams and Eves would never make it full term.
Dr. Carey suggests that a more believeable scenario would be to make the Adams and Eves with an extra copy of a gene, rather than an entire chromosome. Each chromosome carries thousands of genes, influencing many traits. Giving someone an extra chromosome would not be a practical way to increase certain specific traits, as is being attempted in the Adams and Eves. While Dr. Carey says, "At this point, I only know of adverse effects of extra genes," he admits that an extra copy of a specific gene might someday be shown to convey some benefit. But what gene would the government want to add an extra copy of to create its supersoldiers?
We're just beginning to look for genes related to behavioral characteristics. One current area of intense research involves the search for a risk-taking gene. This gene supposedly predisposes one to risk-taking behaviors, like skydiving or becoming an FBI agent. Dr. Carey suggests that such a gene might be valuable in a soldier.
The Adams and Eves, while they are risk takers, aren't exactly the perfect soldiers with their murderous impulses. Perhaps the government gave them the wrong gene. What might it be?
We still have only the vaguest idea about genetic factors that might lead people to become psychotic murderers like the Eves. A recent study is the first to connect a defect in a specific gene with human violence. Dutch geneticist Dr. Han Brunner studied a large Dutch family whose males have been prone to violence for generations. One man raped his sister and was put into a mental institution, where he attacked the warden with a pitchfork. Another man tried to run over his boss. Another threatened his sisters with a knife. Two, upset about the deaths of relatives, set fires. Since none of the women have shown any tendency toward violence, this trait seemed to be X-linked, like Mulder's red-green color blindness. Dr. Brunner discovered that the faulty gene did indeed lie on the X chromosome, and that it produced an enzyme called monoamine oxidase A (MAOA). MAOA helps to break up the neurotransmitters dopamine, epinephrine, norepinephrine, and serotonin. A urine test confirmed that the neurotransmitters were not being broken down in the men. As we discussed in "Ice," neurotransmitters affect our emotions and behavior. In a stressful situation, when the fight-or-flight response is stimulated, excess quantities of these neurotransmitters would build up in the males, intensifying and prolonging aggressive feelings, and perhaps leading to violence. It remains unknown whether this defective gene is a widespread cause of violence or whether environmental factors contributed substantially to the men's behavior. If we want to genetically engineer strong, aggressive soldiers, we have a ways to go. How can we learn more?
While we currently know the function of only a small percentage of our approximately 100,000 genes, we can now "knock out" any gene in a mouse and study its effect. Since humans and mice share 99% of the same genes, this will tell us a lot about human genes. In fact, soon we should be able to insert a switch into a gene, so that we can knock it out when we want, during embryonic development or later, when the mouse has reached adulthood, to see the gene's effect at different stages. The Cigarette-Smoking Man might then insert a gene that would turn on at a certain point, or a switch that would turn a gene off, giving someone cancer or some alien quality at a preprogrammed age. How's that for a nice bedtime story?
[The following discussion covers other experimental implants now in development.]
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Updated June 5, 2003