When they do psychology of everything else, disorders and otherwise, they always want it to come back to the parents and the childhood. They should use the same strategy with sexuality. The "born this way" hypothesis was born out of political expediency and then became unquestionable dogma. Since it's no longer a political necessity -- we each are allowed to choose what we want to be every day now -- it should be discarded by even those who felt the need to ascribe to it before.