By genetics I wasn't making a sweeping generalisation, far from it.

From the 16 years I have worked in IT the people most suited to IT are geeks.  I think that some people are predisposed to become geeks (anyone else remember doing the maths for other kids at Primary in your head?) and some aren't.  There are lots of geeky professions - and IT is one of them.

And IT employers like younger geeks because they are often unattached and prepared to do masses of free work.

It just so happens, from my experience, that the majority of geeks are male. 

Unless IT changes to be less geek-friendly then it won't attract enough non-geeks; and regardless of gender that is a big issue.

You don't have to be a geek to work in IT; but it helps!