Gamma Distribution Parameter α Estimated from Multiple Alignments
| Protein family[i] | Pfam ID | α Estimate |
| Ribulose biphosphate carboxylase, large chain | PF00016 | 0.21 |
| Cytochrome b (N terminal)/b6/petB | PF00032 | 0.22 |
| Hemagglutinin | PF00509 | 0.22 |
| 6-Phosphogluconate dehydrogenase | PF00393 | 0.24 |
| Reverse transcriptase | PF00078 | 0.29 |
| Class I histocompatibility antigen, domains α1 and α2 | PF00129 | 0.29 |
| Retroviral Vpr protein | PF00522 | 0.31 |
| NADH-Ubiquinone/plastoquinone oxidoreductase | PF00361 | 0.35 |
| Average ± standard deviation | — | 0.27 ± 0.05 |
[i] The α values are given only for the largest families that allowed a reliable extrapolation.