I should really... like reaaaally be looking elsewhere for an answer to this but I was already on the site and I thought "hell why not". So here we go.

I've been learning about DNA and what not in my bio class today (it's to fill a sciences requirement, I'm currently in humanities but that's about to change, it's a long story), when the thoughts came to me:

If the 4 chemicals which make up DNA and then RNA are taken by enzymes and used to direct cell activity, thereby developing the body, how are instincts developed? Do the neural connections come pre-packaged? How does DNA code instinctual response? Please help me out with this. It (among others) has been gnawing at my brain all day.

Any other details you can think of please add, I'm too lazy to think up more questions.