The Catechism of the Catholic Church states that homosexuality’s “psychological genesis remains largely unexplained” (#2357). While it is understandable that the writers of the Catechism would not wish to make a definitive statement about a question which is at the center of such a contentious public debate, this statement does not accurately reflect what is known about homosexuality. There is ample evidence that same-sex attraction has many different causes. These lead to significant childhood and adolescent emotional pain and psychological problems. Among males these could include a weak masculine identity, social isolation and loneliness, peer rejection or a poor body image and in females, a mistrust of male love or a weak feminine identity
From my experience I would tend to agree with the CMA here rather than the Catechism. Anyone agree?
It's really not the Catechism's place to pronounce on scientific matters; as I understand it, anyway, to a real scientist there are no scientific facts, only the latest hypothesis, which -- however convincing it appears now -- must be scrapped if even more convincing evidence ever turns up supporting an alternative hypothesis. (Many purported "scientists," of course, have an agenda of their own, but that's a different story.)
Also, even CMA does not claim that there is a single cause operating in each individual case: There is ample evidence that same-sex attraction has many different causes. I think the Catechism was wise to refrain from taking a position on a non-moral matter: the important part of the Catechism's point is that -- regardless of cause -- the inclination is disordered and the act gravely wrong. It might have been even wiser if the Catechism had dropped "psychological" and left it at "genesis."