Are homosexuals born with this disorder? I have never heard a definitive answer on this subject. I believe this behavior is not learned, but if it happens at birth, why would God place such a heavy cross on any human being he created?
Science has not yet established the degree to which homosexual tendencies are learned or inborn. It is likely to be a combination of both factors, like alcoholism is. In the latter case, there is a genetic predisposition to alcoholism, but it takes a process of conditioning and experience with alchohol to develop the addiction.
Sexual drives are built into the human race biologically, but among humans sex is subject to a great deal of cognitive conditioning. Responses to particular stimuli (body shapes, facial features, hair colors, clothing) are largely learned and vary widely from individual to individual, and even from time to time in a single individual's life. This degree of cognitive involvement in sexual behavior is not found among lower life forms, whose sexual behavior is almost entirely instinctual and has few cognitive factors involved in it.
There may be genetic, hormonal, or neurological factors toward which produce a predisposition toward homosexual desires, but some degree of learning and conditioned response is almost certainly involved (as in human sexuality generally). Because of this ambiguity, the Catechism of the Catholic Church states that homosexuality's "psychological genesis remains largely unexplained" (CCC 2357).
It is important to realize that homosexuals do not have complete, voluntary control over their desires. Of course, they have control over their actions, as do heterosexuals. After a person has been conditioned to homosexual responses, it is impossible to simply wish away the desires, just as it is impossible for an alcoholic to wish away his desire to be drunk. (It should be noted that heterosexuals do not have complete control over their desires either.)
Homosexuals also do not make a conscious choice to have homosexual tendencies. Nobody says, "I think I'll become a homosexual!" any more than anyone says, "I think I'll become an alcoholic!" Homosexual desires may come about as a result of certain choices the individual makes (such as thinking about members of the same sex in a certain way or engaging in homosexual behavior), just as alcoholic desires may come about as the result of certain choices the individual has made (such as frequently choosing to get drunk), but virtually no one consciously chooses to become a homosexual or an alchoholic as a goal and then intentionally cultivates the corresponding desires.
For this reason, the Catechism states, "The number of men and women who have deep-seated homosexual tendencies is not negligible. They do not choose their homosexual condition; for most of them it is a trial. They must be accepted with respect, compassion, and sensitivity. Every sign of unjust discrimination in their regard should be avoided. The persons are called to fulfill God's will in their lives and, if they are Christians, to unite to the sacrifice of the Lord's cross the difficulties they may encounter from their condition" (CCC 2358).
While they may not choose their desires, homosexuals do have the ability to choose whether they act on those desires, just as an alcholic has the choice of whether to act on his desire to get drunk and just as a heterosexual has the choice of acting on his desires. For this reason, the Catechism states, "Basing itself on Sacred Scripture, which presents homosexual acts as acts of grave depravity, traditions has always declared that homosexual acts are intrinsically disordered. They are contrary to natural law . . . . Under no circumstances can they be approved . . . . Homosexual persons are called to chastity. By the virtues of self-mastery that teach them inner freedom, at times by the support of disinterested friendship, by prayer and sacramental grace, they can and should gradually and resolutely approach Christian perfection" (CCC 2357, 2359).
Regarding God's involvement in the origin of homosexuality: He is not the source of such temptations, just as he is not the source of temptation in general: "Let no one say when he is tempted, 'I am tempted by God'; for God cannot be tempted with evil and he himself tempts no one" (Jas. 1:13). Adam is the source of the temptations we feel. It is because of his sin that we have inherited a corrupt nature (Rom. 5:19).
