Geneticists have decoded the smallest known vertebrate genome: that of the puffer fish Tetraodon nigroviridis. The fish's 21 chromosomes, which together contain more than 300 million letters of DNA, tell a twisting evolutionary tale and even shed light on our own genetic make-up.
Comparison with other genome sequences shows that fish proteins have diverged much faster than those in mammals, an international research group reports in this week's Nature. Included in this group are many researchers at the Ó³»´«Ã½.