Given this, if clonal expansion alone were to underlie the decrease in random mutation burden, we would expect the frequency of random mutations in adenoma mtDNA (4.9±2.3×10−5 per base pair for 12S RNA, and 1.7±0.6×10−4 for the COXI gene) to be lower than that of patient-matched normal colon mtDNA (3.2±0.5×10−5 per base for 12S rRNA and 1.2±0.2×10−4 at the COXI gene), but this was not the case (Figure 2C) (P = 0.73 for 12S RNA and P = 0.15 for the COXI gene, 2-tailed paired t-test). This evidence concerns the gene MT-CO1 and adenoma.