Just as a matter of clarity, it ought to be noted that according to Christianity, the mere desire to sin is not itself a sin (otherwise "overcoming temptation" is incoherent). Thus what makes someone a homosexual, at least as far as Christians are concerned, is participation in the relevant sexual activities. Even if those who engage in such behavior are born predisposed to have desires for doing so, this does not make acting on those desires any less wrong (anymore than the alcoholic can be excused for the behavior to which he is genetically predisposed).
In terms of the treatment of homosexuals in general, it is certainly the case that they should not be the subjects of hatred and/or genuine perspecution. However, our culture sadly fosters the idea that mere opposition constitutes persecution, and thus dulls the moral sense with which we are endowed. Homosexual behavior should be opposed, though with the humble acknowledgement that our own lives are full of behaviors which ought to be opposed just as strenuously.