I was just thinking, wouldn't the child have a greater chance of birth
defects since bad recessive genes would be paired together? 

Possibly.  Such a mating could well produce Ranma's exact
genotype or one with all of the recessive traits within his DNA (which
would probably be interesting were I a geneticist). 

That depends on if Onna-Ranma and Ranma are genetically similar (which 
I doubt).

The Drowned Girl from the spring is Onna-Ranma's body, since she was 
(supposedly) Chinese and alive a couple-thousand years ago, I doubt 
she's related to Ranma in any appreciable way...

9_9 I thought the Herb storyline cleared that up.  The SOD-Girl
changes it's victims into female versions of themselves, _not_ clones of
the original woman that drowned in it.

Ironic idea. With the possibilities of cloning, males would become
unnecessarry. However, with the SOD-Girl, females would be unnecessarry.

Scary thought.

Damien Roc