"Using this mechanism, we created the world's smallest game board for playing tic-tac-toe, where every move involves molecular self-reconfiguration for swapping in and out hundreds of DNA strands ...

The Tic-Tac-Toe game circumvents this complication by using a second technique called DNA strand displacement. With this approach, scientists again exploit DNA pairing patterns.

Today: Playing tic-tac-toe with DNA origami. Scientists at Caltech have created the world's smallest game board for playing tic-tac-toe out of DNA strands.