So, I’ve decided to get ink. Becuase I’m a biochemist, and an enormous geek, I want to get a DNA double helix. But what exact design should I get? It’ll go on my shoulder blade, and I’ll probably just go for black ink. Oh yeah, and pretty small too, since I’m poor and will probably start crying while I’m getting it.
I’ll go for something stylized (and easily reproduced) but not laughably innacurate, since I’m getting to impress science babes.
You might want to pick a different spot – I’m told that over bone hurts the worst. Of course I didn’t find this out until after I got my little ankle lizard guy. Even so, it wasn’t intolerable. But if you’re worried about pain, I’d say talk to the artist about locations.
I can’t help on finding a pattern, but may I say that sounds like a really cool tattoo idea. 
My best friend has a double helix tat as well, but hers is, as I understand it, a top view. That being said, good luck with the inking!
The first thing that came to mind: Mr. DNA from Jurassic Park
Seriously, something like this? (That’s just a scan of a sharpie drawing.) I think you’ll have a hard time finding something on the web that’s stylized enough.
If I may make a suggestion:
Get it around your bicep, like some people do with the barbed wire tats. The ends don’t have to meet either. In fact, I think it would be kind of cool if the ends went past each other.