Are We Predestined by Our Genes?

“WE USED to think our fate was in the stars. Now we know, in large measure, our fate is in our genes.” So said James Watson, quoted in the beginning of the book Exploding the Gene Myth, by Ruth Hubbard and Elijah Wald. However, immediately below Watson’s quote, R. C. Lewontin, Steven Rose, and Leon J. Kamin are quoted as saying: “We cannot think of any significant human social behavior that is built into our genes in such a way that it cannot be shaped by social conditions.”

The jacket of that book summarizes some of its contents and opens with the crucial question, “Is human behavior genetic?” In other words, is human behavior determined entirely by the genes that mediate the heritable biological characteristics and traits of the organism? Should certain immoral behavior be acceptable on the basis that it is genetic? Should criminals be dealt with as victims of their genetic code, being able to claim diminished responsibility because of a genetic predisposition?

There is no denying that scientists have made many beneficial discoveries in this century. Among these discoveries is fascinating DNA, the so-called blueprint of our genetic makeup. The information the genetic code holds has intrigued scientists and laymen alike. What has research in the field of genetics really discovered? How are findings used to support the modern doctrine of preprogramming or predestination?

What of Infidelity and Homosexuality?

According to an article published in The Australian, some genetic research asserts that “infidelity is probably in our genes. . . . It appears that our cheating hearts are meant to be that way.” Just imagine what havoc this attitude could wreak on marriages and families by creating a loophole for anyone who wants to claim diminished responsibility for a promiscuous life-style!

Regarding homosexuality, Newsweek magazine carried the headline “Born or Bred?” The article stated: “Science and psychiatry are struggling to make sense of new research that suggests that homosexuality may be a matter of genetics, not parenting. . . . In the gay community itself, many welcome the indication that gayness begins in the chromosomes.”

The article then quotes Dr. Richard Pillard, who said: “A genetic component in sexual orientation says, ‘This is not a fault, and it’s not your fault.’” Further strengthening this “no fault” argument, Frederick Whitam, a researcher in homosexuality, observes that “there is a tendency for people, when told that homosexuality is biological, to heave a sigh of relief. It relieves the families and homosexuals of guilt. It also means that society doesn’t have to worry about things like gay teachers.”

Sometimes, so-called evidence that homosexual tendencies are determined by genes is presented by the media as factual and conclusive rather than as a possibility and inconclusive.

The New Statesman & Society magazine puts cold water on some of the flair for rhetoric: “The dazzled reader may well have overlooked the sketchiness of the actual hard physical evidence—or, indeed, the total absence of a basis for the scientifically egregious [flagrant] claim that promiscuity ‘is encoded in the male genes and imprinted on the male brain’s circuitboard.’” In their book Cracking the Code, David Suzuki and Joseph Levine add their concern about current genetic research: “While it is possible to argue that genes influence behavior in a general sense, it is quite another matter to show that a specific gene—or pair of genes, or even a score of genes—actually control specific details of an animal’s responses to its environment. At this point, it is fair to ask whether anyone has found, in the strict molecular sense of locating and manipulating, any stretches of DNA that affect specific behaviors predictably.”

Genes for Alcoholism and Criminality

The study of alcoholism has fascinated many genetic researchers over the years. Some claim that studies have shown that the presence of or the lack of certain genes is responsible for alcoholism. For example, The New England Journal of Medicine reported in 1988 that “during the past decade, three separate investigations have produced conclusive evidence that alcoholism is a heritable trait.”

However, some specialists in the field of addiction are now challenging the view that alcoholism is influenced largely by biological factors. A report in The Boston Globe of April 9, 1996, stated: “There is no alcoholism gene in sight, and some researchers acknowledge that the most they will probably find is a genetic vulnerability that allows some people to drink too much without getting tipsy—a trait that may predispose them to alcoholism.”

The New York Times reported on a conference at the University of Maryland entitled “The Meaning and Significance of Research on Genetics and Criminal Behavior.” The idea of a criminal gene is attractively simple. Many commentators seem eager to jump on the bandwagon. A science writer in The New York Times Magazine said that evil may be “embedded in the coils of chromosomes that our parents pass to us at conception.” An article in The New York Times reported that the constant discussion of genes for criminality creates the impression that crime has “a common origin—an abnormality of the brain.”

Jerome Kagan, a Harvard psychologist, predicts that the time will come when genetic tests will identify children who have a violent streak. Some people suggest that there may be hope for controlling crime through biological manipulation instead of through social reform.

The language used in reports on these speculations about the genetic basis for behavior is often vague and unsure. The book Exploding the Gene Myth tells of a study by Lincoln Eaves, a behavioral geneticist, who said that he found evidence of a genetic cause for depression. After surveying women considered to be prone to depression, Eaves “suggested that [the women’s] depressive outlook and manner may have made such random troubles more likely to happen.” The “random troubles”? The women studied had been “raped, assaulted, or fired from their jobs.” So did depression cause these traumatic events? “What kind of reasoning is that?” continues the book. “The women had been raped, assaulted, or fired from their jobs, and they were depressed. The more traumatic events they had experienced, the more chronic the depression. . . . It might have been worth looking for a genetic link if he [Eaves] had found that the depression was not related to any life experience.”

That same publication says that these stories are “typical of most current reporting on genetics [behavioral], both in the mass media and in scientific journals. They contain a mix of interesting facts, unsupported conjectures, and wild exaggerations of the importance of genes in our lives. A striking thing about much of this writing is its vagueness.” It continues: “There is a big difference between associating genes with conditions that follow a Mendelian pattern of inheritance and using hypothetical genetic ‘tendencies’ to explain complex conditions such as cancer or high blood pressure. Scientists make a further leap when they suggest that genetic research can help to explain human behaviors.”

However, in view of all the foregoing, the oft raised questions still remain: Why do we at times find changed behavior patterns emerging in our lives? And what control do we have in such situations? How do we gain and maintain control of our lives? The next article may prove helpful in providing some answers to these questions.

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Gene Therapy—Have Expectations Been Fulfilled?

What about gene therapy—injecting corrective genes into patients to cure them of inborn genetic diseases? Scientists had high expectations a few years ago. “Is gene therapy a technology whose time has come?” asks The Economist of December 16, 1995, saying: “Judging from its practitioners’ public statements, and much press coverage, you might think so. But a panel of America’s scientific great and good begs to differ. Fourteen eminent scientists were asked by Harold Varmus, the head of the National Institutes of Health (NIH), to review the field. After seven months of cogitation they said in a report published last week that, although gene therapy is promising, its accomplishments to date have been ‘oversold’.” Tests were conducted involving 597 patients suffering from adenosine deaminase (ADA) deficiency or one of a dozen other diseases thought amenable to treatment by the addition of foreign genes. “According to the panel,” says The Economist, “not one of the patients has clearly benefited from participation in such a trial.”

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Despite what some may claim about genetic predisposition, people can choose how they act