Table 1.
Frequency of non-consensus amino acids in each of the β20–β21 residues among 2500 primary HIV-1 strains (All) and among those HIV-1 strains that contain a residue other than leucine at position 193 (L193x)
| Residue | All (%) | L193x (%) | Enrichmenta | Residue | All (%) | L193x (%) | Enrichment |
|---|---|---|---|---|---|---|---|
| I420x | 1 | 2 | 2 | E429x | 55 | 39 | 0.7 |
| K421x | 8 | 6 | 0.75 | V430x | 10 | 12 | 1.2 |
| Q422x | 1 | 2 | 2 | G431x | 1 | 2 | 2 |
| I423xb | 9.5 | 29 | 3.1 | K432x | 61 | 43 | 0.7 |
| I424x | 25 | 33 | 1.3 | A433x | 2 | 2 | 1 |
| N425x | 9 | 14 | 1.6 | M434x | 12 | 6 | 0.5 |
| M426x | 16 | 27 | 1.7 | Y435x | 1 | 0 | 0 |
| W427x | 1 | 0 | 0 | ||||
| Q428x | 2 | 2 | 1 | Average | 1.2 |
aEnrichment, ratio of the frequency among non-leucine 193 HIV-1 strains to the frequency among all HIV-1 strains. The values associated with the maximal enrichment are indicated in bold.
bP value < 0.00001 in a two-tailed t test for the difference between the enrichment of I423x and other residues