Letters to the Editor 19171 Share this: Share via email (Opens in new window) Email Click to share on Facebook (Opens in new window) Facebook Click to share on Reddit (Opens in new window) Reddit Click to share on X (Opens in new window) X Click to print (Opens in new window) Print By Science News January 22, 2003 at 10:43 pm After reading this article, I couldn’t believe that the manuscript didn’t identify the chemical substance involved. Eck Prud’hommeFort Worth, Texas The amino acid mentioned in the story is p -aminophenylalanine .–J. Gorman