Table 3.
Test of independence between different codon positions in the 4-fold degenerate families.
| Amino acids | Codons | p Value * | |
|---|---|---|---|
| Genome | psbA | ||
| Leu/Pro/Arg | CTN/CCN/CGN | p < 0.001 | p = 0.062 |
| Val/Ala/Gly | GTN/GCN/GGN | p < 0.001 | p = 0.026 |
| Leu + Val/Ser + Pro + Thr + Ala/Arg + Gly | CTN + GTN/NCN/CGN + GGN | p < 0.001 | p < 0.001 |
| Leu/Val | CTN/GTN | p < 0.001 | p = 1.000 |
| Arg/Gly | CGN/GGN | p = 0.021 | p = 0.597 |
| Ser/Pro/Thr/Ala | TCN/CCN/ACN/GCN | p < 0.001 | p = 0.125 |
* Pearson’s Chi-square test was used for genome data and Fisher’s exact test was used for gene data. Significant p values after Benjamini–Hochberg correction are marked in bold (FDR = 0.05).