I did state that it's as low as 1 in 500 (some have even said as low as one in 300). The number of people that are *noticeably* different is rather lower, though. I would not be terribly surprised to find my own chromosones are a bit unusual, but I've never bothered to have them checked.

The exact words listed above were 'hermaphrodite and things' and yes - it is insulting, even if the proper term intersex was used. The reason I'm not including transgender, is that it's a very general term, and unless the person in question knows for a fact they have a chromosonal abnormality they may not qualify under the biological definition the lecturer appeared to be using.

I take a somewhat wider view of gender and sex than that.