[VxH]

>>People affected by this are not disfigured

Are they reproductively viable without medical intervention?

What is the net effect of reproductive fitness on groups containing a high incidence of this mutation?

[js1138]

I don't think this is a mutation in the usual sense of the word, although I would defer to the biologists on this one. I do know from my background in special education that people with anomalous chrosomes are usually, but not always, sterile.

Sex is not always fixed in animals. The clownfish father in "Finding Nemo" would, in real life, have turned into a female upon the death of his mate.

[Mr. Bird]

Are they reproductively viable without medical intervention?

Many who have these conditions have what is called "streaked" gonads; meaning they are not functional. The androgen insensitivity syndrome will cause this, as will it's converse, fetal androgen syndrome, which is when female embryos are affected by testosterone from a fraternal (boy) twin.

The short answer to your question is that the truly complex cases are not able to reproduce, with or without medical intervention.

[Mr. Bird]

If you know any cattle farmers, ask them about freemartins. It's the cow equivalent to this discussion.