Mutations in the H-Ras gene. Representative examples of somatic mutations in the H-Ras cDNA from primary mammary tumors of the MMTV-Wnt1 mice. Sequence chromatograms of codons 12, 13, and 61 are shown as they appear in the forward and reverse sequencing directions. Mutant peaks are indicated by arrows. The nucleotide and amino acid alterations are indicated on the right.