A high percentage of Candida albicans CTG codons are represented by serine residues in the Saccharomyces cerevisiaeand Schizosaccharomyces pombe genomes. To determine the origin of leucine codons present in the C. albicans genome, the percentage of serine and leucine residues present simultaneously in theS. cerevisiae and S. pombe genomes was determined for each of the six leucine codons present in the C. albicansgenome. For this, the three genomes were compared using the BLASTP program as in Figures 8 and 9. The conservation of CTN codons betweenC. albicans and S. cerevisiae/S. pombe is very low and reaches the lowest value for CTG codons (0%). Interestingly, 14% of the C. albicans CTG codons encode serine residues and only 0.7% encode leucine residues in S. cerevisiae and S. pombe. This trend is not observed for any other leucine codon; leucine is always highly conserved in homologous S. cerevisiae/S. pombe genes.