In the course of the public debates about use of third-party gametes (particularly what are commonly called “sperm donors”) those opposed often raise the specter of “accidental incest.” (One of the more well-known instances is here, and it’s particularly notable for three reasons: It got a ton of press, it really has nothing to do with use of third-party gametes as it’s about adopted-out siblings, and it is quite possible that it never happened.)
In any event, the idea is that if people do not know they are genetically related then siblings (like the possibly mythical twins who were adopted out into different families) might unwittingly meet, fall in love and have children. I’ve read, in fact, that the affinity arising from the genetic similarity might even make it more likely that siblings would feel attracted to each other, though I have no idea if this is the case.
I don’t mean to dismiss this risk out of hand. It’s obviously possible. The twins story may not be true, but it could be true. And the problem is clearly exacerbated when you have men providing sperm to create scores of offspring. Indeed, concerns about unintentional incest are most often raised precisely in this context. And for what it is worth, I am fine with limiting the number of children who can be conceived with any particular providers sperm (or eggs, but that’s less an issue.)
Now what brings this all up right now is this report from the Hay Festival. Professor Susan Golombok appeared there. She’s a woman whose work I really admire. And, according to press reports, she expressed some concern about the risks of accidental incest. Continue reading →