Reading Between the Lines (IMAGE) Arizona State University Caption As a single chemical base of DNA (blue atoms) passes through a tiny, 2.5nm gap between two gold electrodes (top and bottom), it momentarily sticks to the electrodes (purple bonds) and a small increase in the current is detected. Each of the chemical bases of the DNA genetic code, abbreviated A, C, T or G, gives a unique electrical signature as they pass between the electrodes. Credit Biodesign Institute at Arizona State University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.