So let’s look at the state of true scientific inquiry into how homosexuality presents itself in human beings.
First, twin studies. Recent studies have found that when one identical twin is gay, there is a 52 percent chance the other is also gay; if one fraternal twin is gay, the probability the other twin is gay drops to 22 percent; and if one separate-birth sibling is gay, there is only a 6 percent to 10 percent chance another sibling will be gay. This indicates both heritability and that something environmental (probably hormone levels in utero) is at play. This is reinforced by the fact that more recent studies have indicated that when identical twins share an amniotic sack, they nearly always have the same orientation, gay or straight.
Look also at studies on fraternal birth order. Ray Blanchard and colleagues discovered accidentally that each time a woman gives birth to a son, the chance that the boy will be gay increases by about 30 percent. Older sisters do not affect the probability, only older brothers. Blanchard argues that this indicates an immunoresponse by the mother to the presence of a male child.
There are also studies that have shown differences in finger length between heterosexuals and homosexuals. The results of these studies have been verified and reproduced.
Sexuality is about as much a “choice” as handedness is.
As recently as the last century, teachers would tie a child’s left hand in a vain attempt to make them right-handed. While a left-handed person can force himself to write right-handed, just as a gay person can force himself to live a heterosexual lifestyle, that doesn’t make the leftie a rightie or the gay man straight. Some people (the ambidextrous or the bisexual) would find it relatively easy to move from one behavior to the other, but for most of us, changing our sexuality would be as impossible as learning to write as precisely or throw a ball as accurately with our non-dominant hand as with our dominant hand.
Science doesn’t have “proof” as to what causes left-handedness, either. Like sexuality, it is probably a combination of genetics and in utero environmental factors, reinforced in early childhood by societal norms. But it’s clear that both are most likely fixed at birth.
Busey has done the readers of the Redding Record Searchlight a great disservice by presenting his misguided opinions as being representative of the scientific community at large.
Sexuality is not strictly a genetic trait, like skin color or eye color, but it is certainly not a conscious choice people make. Even if it were, that’s still no reason to deny marriage equality to the more than 1 million gay people living in California. Religion is a choice, and laws prevent discrimination on that basis.