Opposing the happiness of the incestious is intolerant, haters!
Although the resulting babies would inherit a small fraction of their DNA from the donor and not their mother or father, the procedure would spare all future generations from a host of rare and debilitating conditions.
And there was much mutant rejoicing.
I guess this isn’t so funny to those of you with opposite-sex siblings. But I have no sister. Thus the thought of bro/sis unions is less offputting than gay marriage, less intriguing than lesbian marriage. But none of these three trigger absolute “I’d-rather-die” intolerance.
That’s reserved for Feds meddling in social matters for which it has no Constitutional authority.