In X-Men the Last Stand, a mutant cure is discovered that would presumably turn mutants into normal human beings permanently. X-Men is a strong analogy for the gay community and the plot therefore is topical for them. There are rumors of China successfully changing the sexuality of mice like an on/off switch and no doubt they will eventually find a "cure" for humans within this century.
1. Magneto: If homosexuality/transsexualism can be cured with a pill, it will be forced upon the LGBT community legally or with high social pressure. The psychiatric community has already banned the practice of trying to convert someone's orientation. Therefore, if the cure is discovered, it should be banned none-the-less. In extreme cases, force must be used to stop the production and/or distribution of the cure.
2. Rogue: The cure should be allowed to be prescribed freely to those who want it. Some would immediately take the cure and have no ethical qualms taking it.
3. Angel: Some would rather not take the cure but feel overwhelming family pressure to take the cure. Therefore, a psychiatric evaluations should be required to make sure the individual is freely choosing the cure.
4. Xavier: The cure should not be prevented from being made, those who are LGBT should not be ashamed of it, but those who wish to use the cure should be free to do so, but society should not force it upon them. In any case, non-violence is the rule.
Characters that undergo transition are often uplifted as being courageous. Is the opposite true for someone who would take such a cure? Collective solidarity vs individual choice?