Ellynne:

The problem with this (as it relates to humans) is that most cases of a single chromosome lead to fatal or severely damaging defects and deformities.

Don't forget the Auronar have already sussed human cloning, which implies a fairly advanced degree of knowing-what-they're-doingness. Gene expression patterns are very dependent on precise extracellular milieu (both chemicals and physical contacts).

I think single X's are survivable but severe.

Yes. XO is female but sterile.

Y's sans X are invariably fatal). This makes sense given that the Y chromosome is shorter than the X, so the normal gene balance can't take place.

I did briefly wonder whether this might be why all the clones we see are female. But surely one could engineer an X-primed chromosome which both contained all the essential genes on X *and* switched to male patterning.

Tavia