on four chromosomes in mice selected for glycine preference, and linkages on five chromosomes for mice selected for saccharin intake. We have found the complex genetic architecture of sweetener preferences, with each progenitor strain contributing loci increasing or decreasing a trait value, and with two distinct sets of genes for glycine and saccharin consumption.[138-140] Consistent with our genetic mapping studies, mice with mutations in genes other than taste receptors also have altered behavioural responses to sweeteners.[141-145] Furthermore, taste responses to complex carbohydrates (malto oligosaccharide and Polycose) are not affected by allelic variants of the Tas1r3 gene.[131,146,147]
