Abstract
Mice of WVWV, WWV and Wvw genotypes, unlike other mice, excrete the D-isomers of phenylalanine, tyrosine, tryptophan, methionine, and histidine when the D and L isomers of these amino acids are fed. Ww and ww mice, however, otherwise genetically similar to the above, are able to utilize both the D ana L isomers of these amino acids.