Right when I saw a pair of these on Etsy (http://www.etsy.com/listing/51730736/rainbow-genes-free-shipping), I had to make them!
The photos are a lil blurry, so if you have any questions about the how-to just ask. :)
Start by making the rungs of the double helix.
Thread beads onto eye pin. I used 4 tube beads (two in each color for the nucleotides).
Using the jewelry pliers make a loop at the other end of the eye pin.
Your rung should now have two loops, one on each end.
Repeat steps 1-3 until you have 10 rungs.
Grab two head pins. Thread one 4mm seed bead on each pin. Then, thread one of your rungs.
Repeat step 5, alternating between seed bead and rung until you have used all 10 rungs.
Using the pliers, make an oblong loop with the remaining ends of the head pins.
Push the oblong loops together until they overlap. Open the loop of the earring hook with the pliers. Slide the two loops onto the earring hook.
The red and blue are the oblong loops, and the gray is the earring hook loop.
Twist the ladder!
And you have one of your earrings. Repeat steps 1-9 to complete the pair.