Table 3. Amino acid substitutions in the non-structural proteins encoded by orf3a and orf6 genes of SARS-CoV-2 isolated from animals compared to humans.
| Gene | Amino acid position | SARS-CoV-2 Reference | Cat | Dog | Mink | Mouse | Tiger | Human |
|---|---|---|---|---|---|---|---|---|
| orf3aA | 57 | Q | Q | Q | H (25.9) | Q | H | Q or H |
| 182 | H | H | H | L (3.4) Y (22.4) |
H | H | H | |
| 219 | L | L | L | V (25.6) | L | L | L | |
| 224 | G | G | G | C (2.7) | G | G | G | |
| 229 | T | T | T | I (16.3) | T | T | T | |
| 251 | G | G | V (50.0) | G | G | G | G or V | |
| orf6B | 20 | R | R | R | S (10.2) | R | R | R |
| 23 | K | K | K | S (2.0) | K | K | K |
Notes:
A
orf3a, open reading frame 3a.
B
ns3a, Non-structural protein 3a.
The numbers in brackets represent the percentage of genomes that contain the substitution. For example, the substitution of amino acid number 219 of ns3a protein (encoded by orf3a) from L to V (L219V) in mink occurred in 25.6% of mink isolates. Percentages are reported for substitutions only. Substitutions that existed in less than 2% of the genomes are not reported. Unique mutations for an animal species are highlighted in yellow.