Born this way, baby

[Silver]

Yes, there's a genetic part and an environmental part. I submit to you that this is vastly different than the "choice" that the christian right wants you to believe it is.

Indeed. I believe this one article summed it up rather nicely in its conclusion:

This chapter started with a comment on evidence. One is also appropriate here: those who argue against a biological basis for sexual orientation often cite studies of negative findings that supposedly refute those of positive findings (e.g., Byne 1994; Byne & Parsons 1993). It is rare in biology or behavior to find all research to agree in every aspect of a long-running controversy. That is the nature of the controversy. If all evidence pointed in one direction, only the prejudiced would continue the debate. The behavioral and sexological sciences are not perfect. Argument by “objection” or “call for perfection” certainly might prompt additional research but will not yield solutions, nor do they really disprove a theory (Fearnside & Holther 1959).The opposition needs to do more: it needs to present strong alternative hypotheses with controlled research and data sufficient to substantiate them.

Looked at from another angle it can be asked, if sexual orientation is so easily modified by environmental forces, why don’t we readily see its effect? Why is not therapy to change homosexual to heterosexual behavior readily successful even when started early and when parents and the individual are eager for such change (Green 1987)? If the basis for homosexual behavior is some set of environmental forces, why are these factors not only so difficult to identify but impossible to bolster with reliable and consistent findings? Those environmental forces most under suspicion have been looked for and found wanting. Certainly particular stages or critical periods in development seem more significant than others in organizing and activating these behaviors. Perhaps we have to be more sophisticated in selecting time periods to investigate or developing techniques of investigation.

For some persons, the idea that sexual orientation is biologically biased toward heterosexuality or homosexuality and predisposed is threatening. They would like to think the choice is open and always fresh. This is more often a political stance than a scientific one.

http://www.hawaii.edu/PCSS/biblio/articl...pects.html