I can certainly understand your worries.
Maybe I can provide some perspective.
This research has been going on for years, and some scientists think they may be close to identifying the genetic markers that control sexuality.
However, I would like you to consider two things.
1. Children are not generally screened for genetic markers that are not linked to health issues. This is not to say that it can't be used in this fashion, but genetic testing is costly and not used lightly.
2. (And this, I feel, is much more important). Pretty much everything we are (aside from learned behaviors) is a result of our genetics. How great would it be to determine once and for all that the reason a person has a particular sexual orientation is the same reason they have blue eyes? And just as stupid a thing to hate someone over?
To shut up all of those (IMO) idiots that think that being L/G/B/T is a "choice", and you can "choose" not to be one thing or another?
I am straight myself, and I could no sooner "choose" to be Gay than my good friend Jay could "choose" to be Straight.
Can a Black person "choose" to be White or a tall person "choose" to be short? Of course not - and why should they want to?
People are people. And sexuality is no more a choice than any other naturally occurring feature. Every "non-Straight" person I have ever known (and there have been a lot of them)
knew they were L/G/B/T at a very early age.
Their personal experiences will only be confirmed by research that determines that our sexuality is determined in the same way our hair color is.