Dan Kuebler argues that even if human sexual orientation was genetically determined (and we don't know if it is), it wouldn't justify support for same-sex marriage.

Memo to Lady Gaga: "Born This Way" Doesn't Mean "Act This Way"

by Daniel Kuebler

It remains unclear whether sexual orientation is genetically determined. 

Even if it is, that doesn't justify advocacy for same-sex marriage.

A growing laissez-faire libertarian attitude toward social issues among Americans is arguably the most important weapon available to same-sex marriage advocates. Certainly there are LGBT militants with unwavering commitment to the issue, but the vast majority of those who "support" same-sex marriage can hardly be said to support anything. They just have a hard time saying no. They much prefer the sanitary hands off approach--let them live out their sexuality as long as I don't have to get involved.
This laissez-faire attitude is often coupled with a heavy dose of biological determinism, which bestows a tacit scientific stamp of approval on any and all types of sexual behavior. Consider Lady Gaga's popular song, "Born this Way," in which she sings, "Cause baby, you were born this way, no matter gay, straight or bi, lesbian, transgendered." She then encourages people to, among other things, embrace whatever sexual proclivities they have inherited.
The underlying message is that we as a society should just accept any and all manifestations of sexual orientation and sexual behavior because people are merely acting upon their God-given biological inclinations. The end result for those saturated in this cultural marinade is that they are afraid to refuse the designation of marriage to same-sex couples who are only doing what comes "naturally" to them.
There are two problems with this type of reasoning. 

• First, it's questionable whether sexual orientation is biologically determined. 
• Second, even if genetic and developmental factors cause one to have same-sex attractions, it does not follow that one's biology should determine one's behavior, much less dictate one's morality.

In the last twenty years, scientific research has failed to generate a consensus on the exact relationship between biological factors and same-sex attractions. But there is general agreement that genetic/developmental factors do have an influence.
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