Nature Methods replies:

We agree with Albrecht that color blindness in readers is an important but often overlooked consideration when authors choose figure colors1. In 2007 Nature Publishing Group began recommending that authors choose color combinations other than green and red when they prepare their manuscripts for submission. Before accepting any manuscript, we again ask authors to recolor red-and-green graphs, schematics and models in which the colors are arbitrary. Unfortunately, as can be seen in the pages of this issue and issues of other Nature Publishing Group journals, there are still instances of red and green being used in a manner inconsistent with these guidelines. We hope to highlight this issue in a future Points of View column that provides more detailed guidelines on choosing colors that are accessible to our readers with color blindness. In the meantime, we encourage authors to visit http://www.vischeck.com/ for more information and to download their free Photoshop and ImageJ plug-ins for recoloring images.