The Article That Started It All...
In 1993, a genetic researcher by the name of Dean Hamer and his associates at the National Institute of Health published an article about an experiment they had conducted to find out if there was genetic influence associated with human male homosexuality. The study began with a subject pool of several self-proclaimed homosexual men and their families. After performing a pedigree analysis on the subjects, it was found that many of the subjects had other gay males in their families related to them maternally. With this new discovery, an offshoot of the experiment was designed to test for a homosexual gene linkage on the X chromosome (always inherited from the mother). Hamer and company limited the subject pool to 38 pairs of homosexual brothers and their mothers (when was available), and their findings were promising. Using their results from linkage and statistical analysis techniques, the research team from NIH concluded that "one form of male homosexuality is preferentially transmitted through the maternal side and is genetically linked to chromosomal region Xq28" (Hamer et al, 1993). They found their results to be statistically significant with a greater than 99% confidence. (Hamer et al, 1993)
Though the statistical results from the experiment were very convincing, and the research team clearly made a conclusion based on that data, Hamer and his associates were careful to include words of caution in their article. Not once in the article was there a claim that the findings illustrated were definite, and there was an affirmation for the need to replicate and confirm the results. It was also noted that more specific mapping would be required, and that by no means did this particular study try to incorporate all potential genetic causes of homosexuality. In fact, the article insists that the subjects of the experiment were only a limited sample size of the gay population, and that other factors (environmental, social, etc.) were not to be ruled out, but rather that the findings from the experiment suggest a genetic predisposition towards male homosexuality.
Dean Hamer, leader of the research and the experiment to find the "gay gene"; Link
Chromosome X, the region q28 where Hamer et al believed the "gay gene" to be present is within the red box; Link
Naturally, results and conclusions from scientific experiments like the one mentioned above generate quite a buzz in the media. The social, political, and ethical debates about homosexuals and gay rights have been huge issues, in the past two decades especially, and that did nothing but to fuel the enthusiasm of popular media sources. As is to be expected, articles in popular magazines written about Hamer and company's findings were numerous and from all angles. Here are some examples of articles that were written after Hamer and his team published their findings that demonstrate the wide range of focus and credibility exhibited by different media sources:
Does DNA Make Some Men Gay? (by Sharon Begley et al; from Newsweek)
In this article, published in 1993, Hamer and his team's results were shared with the public. It outlines the basis of the experiment very briefly. Begley does make sure to include in her article that the specific gene for male homosexuality had not been pinpointed and that the region found on the X chromosome by the research team is "not the only cause of homosexuality" (Begley, 1993).
But even that quotation illustrates the difference in the original scientific journal article and popular media. Even when half-heartedly acknowledging that the findings of the NIH team were not definitive, the choice of words and use of language leave an overall tone that suggests otherwise. In the statement above, by saying the findings of Hamer and company are "not the only cause of homosexuality" implies to the reader that the the region on the X chromosome defined by Hamer and his associates is a direct cause of homosexuality. Along with statements like "strongest evidence yet" and wonderings about what the gene will turn out to be, there is never an inkling of doubt in the whole article that the results and conclusions from the study could be wrong. There are none of the acknowledgements that the experiment needs to be replicated that are found in the original Science article.
The article also talks about how the same team is looking for DNA markers in lesbian women as well, but leaves the topic open. It is not clear to the reader that the research done in the given experiment was only done with a select sample of gay men.
Another interesting difference between this article and the article published by Hamer et al is that Begley touches on the social implications of the new findings, talking about how it may both help and hurt homosexuals in society. On one hand, there may be less discrimination against homosexuals because they would no longer be seen as "deviants." Homosexuality would be seen as something you were born with, not something you choose, much like eye color or height. The flip side of this opinion is that if a gay gene were found, many people may start to consider homosexuality a type of genetic disorder or disease. This raises all kinds of scenarios in which people may try to "cure" or prevent gayness.
Is there a 'gay gene'? (by Traci Watson et al; from U.S. News and World Report)
This article, first published in U.S. News and World Report, has a very different tone than the previous one from Newsweek. Throughout the whole article, the authors constantly make clear that the findings of Hamer and his associates are anything but definite. Other than referring to the conclusions the NIH team made as "a definite 'maybe,'" the article also discusses the dispute among scientists over whether or not the data from the experiment is verifiable. While Watson and the coauthors divulge some of the statistics and conclusions from Hamer's experiment, they also talk about how the results Hamer and his team found may have been skewed, and how the work needed to be replicated.
Also, like the article from Newsweek, the authors of this article also talk about the broader scope and implications of the possibility of a gay gene. It discusses how many prejudices and arguments against homosexuals and their rights would no longer carry any weight, because they would be "born that way." However, the possibility of women having abortions because their child has the gay gene or the idea of gene therapy to "cure" homosexuality would become an issue. To illustrate that point, the authors refer to a man from the Traditional Values Coalition that made a statement saying that "were sexuality ever proved to be rooted in genes, the response should be to find a cure" (Watson et al).
As it turns out, Hamer and his associates were put under investigation by the Office of Research Integrity. No other researchers were able to reproduce the results that they had found. Other experiments with larger sample sizes found much lower rates of concordance among gay men, and none were deemed statistically significant (Rice et al, 1999). Reasons for the disagreement of the data are unknown, but some scientists say Hamer and his team were too selective in deciding their sample group, and others say the results could simply have been a false positive (in regard to Hamer). In any case, the findings of Hamer and his associates at NIH in regard to a linkage between DNA markers on the X chromosome and male sexual orientation have been shown to be unreliable. However, it is important to note that because the Hamer group's results could not be reproduced does not necessarily mean that there is no genetic determination of human sexuality. It is possible that there is a gene or number of genes that may cause a genetic predisposition toward homosexuality, but it has yet to be discovered.
Articles written in popular media sources cover a wide spectrum of topics with varying amounts of reliability. Though many of the articles state the truth, their use of words and emphasis can convey a message that is not necessarily trustworthy. However, this is not always the case, as shown above with the article by Watson et al. Also important to consider is that popular media has a very different reading audience from scientific journals. This explains why many of the specifics of the experiment are left out as well as the focus on social implications of the experiment's results and conclusions. The bottom line is: take information you glean from popular media sources with a grain of salt. Some of it may be true, or all of it may be true, but often the real meaning and significance of actual scientific information is not clear and the "big picture" perspective is lost. No scientific findings are ever definitive, and if all else fails be sure to read the published peer-reviewed journal article that the popular media cites in order to find out all relevant information.
Begley et al. Does DNA make some men gay? Newsweek 1993 July 26; v122; Issue 4
Hamer et al. A linkage between DNA markers on the X chromosome and male sexual orientation. Science 1993 Jul 16; v261; Issue 5119
Rice et al. Male Homosexuality: Absence of Linkage to Microsatellite Markers at Xq28. Science 1999 April 23; v284; Issue 5414
Watson et al. Is there a 'gay gene'? U.S. News and World Report 1995 November 13; v119
© Copyright 2008 Department of Biology, Davidson College, Davidson, NC 28036
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