I think that to believe the sexual attraction can be attributed to genetics is really wrong. I think there is so much more to attraction then just the genes. Personality and a lot of other factors are what can make two different people attracted to each other sexually. It's not genes.
Sexual attraction is a function of the way the body works. Saying that genetic sexual attraction is morally objectionable is like saying that the need to eat, sleep, urinate, or defecate is morally objectionable. All are simply bodily functions which one must adhere to in order to stay alive. Genetic sexual attraction may not strictly be necessary in order to stay alive, but it is simply another bodily function, with no morality attached to it.
No, being sexually attracted to a certain type of person is in our of our genes, and is the only reason we are even here. The reason we are born is to have more offspring and pass on our genes, so no there is nothing morally wrong with sexual attraction.
No, I don't think that genetic sexual attraction is morally objectionable. That's like asking if I think that breathing is morally objectionable, it's a senseless question. Attraction is based on many factors. Some of them may be genetic. But the simple truth is we can't help who we're attracted to.
Genetic sexual attraction is something that was studied related to adoptions. The study assumes that people are naturally attracted to people like themselves. In adoption people are removed from their family at a young age, but they may run into family members (unknown to them) in their adult life and be attracted to these family members. This doesn't happen when family members are raised together, so the idea of genetic sexual attraction has to do with adoption and running into family members that you are not aware of, it's not something morally objectionable, its just a scientific fact, it has no bearing on acting on the attraction.