At first glance the Ettin genome seems not to be very different from the Norn genome. However, Ettins aren't just a poor copy of Norns. Here a few differences between them:
Ettins have 20 organs (Norns 21). As this "missing" organ isn't vital, you won't notice much difference in the game.
Ettins have less receptor genes. The most important difference is maybe, that they don't have receptor genes for antigene 3 - 7, therefore the risk for infections for Ettins is smaller than for Norns.
Reaction and emitter genes are also a bit different than the ones in Norns. The most notably difference maybe is the lack of on reaction gene that enables the creature to lower it's sexual drive. If you've got a male Ettin in your game (the Ettin mother only lays female eggs) and if he's sexually mature he will kisspop over and over again! Sometimes he can get on female Ettin's nerves, believe me! :-)
Ettins can reproduce when reaching stage "adult". But they get older quicker than Norns do.
The number of pose and gait genes is almost identical to the Norn genome. However, there are some differences. But I'm not going to list all of those 242 genes. Maybe a small example? There's a pose called "hit norns". Well, doesn't sound nice, does it? Maybe would be better if it was called "hi Grendels"?:-))
Let's get to the stimuli
genes. I had a closer look at them. It looks like they're bound
to run away from almost everything. If they get pet by another
creature they will go away as well as when they get pet by the
hand. They can get homesick and bored quite easily. Only when
they get machines and drag them around with them the "boredom"
will get reduced. And to satisfy their homesickness they are
looking for "ettin home". All in all Ettins are "programmed"
to be constantly on the walk, looking for some distraction and
also for some comfort. This might be the reason why Ettins wander
around in the ship a lot, as we see it in the game.
Strange enough, the stimulus gene "bump in wall" is
set in order they won't learn to avoid it. I think that's the
reason why we think Ettins are more stupid than norns, but that's
not true!