Genes can variously express themselves. In order to do this, the coding on the gene itself must change in subtle ways thereby changing gene expression a little. The different genetic expressions producing these variances are termed alleles. On the right, four genes are represented. R, O, S and E. The different expressions of these different letters represent different alleles of each letter or, in a genetic sense, each gene. Click on the ALLELE button to see the four groups of alleles.
