Finding new ways to spell L-I-F-E

XNA molecules join DNA and RNA in the genetic catalog

2012 SCIENCE NEWS TOP 25: 11

Life’s menagerie of hereditary molecules got a little bigger this year. By replacing the sugars in the backbone of a DNA strand with other molecules, scientists created ANA, TNA, HNA, FANA, CeNA and LNA (SN: 5/19/12, p.