It is perfectly obvious from your report that Dr Watson, like many people, is simply an advocate of women having the choice. The point of his "gay" gene example was that if you are really committed to giving each woman the choice, you cannot dictate how she will exercise it.
Dr Watson names abilities in music and basketball, not because he advocates selective abortion in their favour, but precisely to emphasise the irrelevance of what he, or anybody else except the woman concerned, thinks, given a pro-choice stance.
A woman might passionately desire a homosexual child and elect to abort a foetus with heterosexual genes. Indeed, I have not the slightest doubt that Dr Watson would be happy to add heterosexuality to his list of hypothetical reasons for aborting.
It is entirely consistent that the anti-abortion lobby has attacked him. It would be logical for a fathers' lobby (and I might join them) to protest that Dr Watson gives too much prominence to the mother's wishes alone. But it is totally illogical for the gay lobby to attack him as, according to your report, they have.
New College, Oxford