The legacy of this is not difficult to see. I've noticed that Christian parents of gay and lesbian children often react as though homosexuality was a much greater tragedy than any other sinful inclination. Part of the reason for this, as Foucault very aptly describes it, is that “The...homosexual became a personage, a past, a case history, and a childhood, in addition to being a type of life, a life form, an amorphology, with an indiscreet anatomy and possibly a mysterious physiology. Nothing that went into his total composition was unaffected by his sexuality. It was everywhere present in him: at the root of all his actions because it was their insidious and indefinitely active principle...It was consubstantial with him, less as a habitual sin than as a singular nature.” Realizing that not everyone speaks Foucauldian, I should clarify that what he's saying is that the Middle Ages understood sodomy as a class of sin, an act which a person might engage in, whereas in the modern era we have come to think of homosexuality as a condition which effects a person in their entirety. Their childhood and the way in which they were raised is therefore naturally implicated. For the parents of LGBTQ kids, this means that their child's sexual inclinations are not merely temptations, and not even merely a disorder, they are the evidence of personal failure on the part of the parents themselves.
Christianity construes responsibility in a different way which I think could be much more helpful to parents of homosexual children than the guilt-saturated models. The tendency to accuse the parents for the sufferings of the child is not new: there is a striking example in the New Testament. “Rabbi, who sinned, this man or his parents, for him to have been born blind?” The disciples ask Jesus in the 9th Chapter of John. Christ replies, “Neither he nor his parents sinned. He was born blind so that the works of God might be displayed in him. As long as the day lasts I must carry out the works of the one who sent me.” Christ dismisses the question of who is responsible for the blindness of this man in terms of blame, and moves immediately to a discussion of who is responsible in terms of healing. His attitude is not that the person who is responsible must make amends, but rather that the person who is able to fix the problem is responsible for doing so. He creates a different kind of narrative, a narrative of restoration in which the blindness of the man becomes a locus of grace rather than an indictment for past sin.
For the parents and families of people with same-sex attraction, I think that this same principle can be applied. There are many ways in which parents and relatives of homosexual people are inclined to apply blame. Some feel that a son or daughter's homosexuality means that they were bad parents, others become resentful and try to escape from a sense of personal guilt by arguing that the gay or lesbian child is responsible for their own condition, while still others push the guilt further away, blaming homosexual partners or a gay-friendly culture for corrupting their beloved child. I think that instead it is more useful to focus on looking for ways that a child's homosexuality can become an opportunity for grace. The genesis of homosexuality is, as the Catechism points out, unknown. It is also not especially important. The much greater and more essential truth is that this too is a way in which the works of God might be displayed in a human life, and that we are all called to take responsibility – not blame – for “All are responsible for all.” (Dostoevsky, The Brothers Karamazov)