The study involved 409 pairs of homosexual brothers. Genome-wide analyses showed strong evidence, the researchers claimed, that two chromosomes, X and chromosome 8, mediated homosexuality based on the genes they shared.
For some experts, particularly those involved with the work, the findings had “landmark” written all over them. But for those less optimistic, the study was flimsy and statistically mediocre, if outright insignificant. Even Dr. Alan Sanders, a behavioral genetics researcher at NorthShore University HealthSystem Research Institute and the study’s lead author, said the evidence “is not proof, but it’s a pretty good indication” that genes wield some influence on sexuality.
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“It can say, ‘Given this sort of genetic information it turns out that this leads to this sort of probability that the person will consciously experience these kinds of sexual attractions,” Earp told Medical Daily.
What it can’t say is, here is this chromosome and it’s the gay chromosome, and we know this because a large number of gay men all share this gene. The model unhelpfully leaves out entire swaths of personal life experience dealing with social interactions, upbringing, environmental factors like political climates and geography, and, indeed, other genes.
This is why the “Born this way” argument tends to fall apart for Earp.
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Ultimately, the search for a “gay gene” is just another player complicit in that argument, and perhaps a dangerous one if the research proceeds far enough. In cellular models, for instance, scientists have already found genetic on-off switches for things like cancer, aging, and certain autoimmune diseases. The field of epigenetics devotes great resources to targeting these abnormalities, and locating a “gay gene” would only legitimize sexuality as something to be studied in a lab, rather than a social and biological phenomenon as clinically uninteresting as hair color or height.