Table 3.

Changes in hydropathy at several Env positions are correlated with in utero mother-to-child transmission^a

^aShown are the individual amino acid (aa) positions, according to HXB2 numbering, and the corresponding subdomain of Env where that position is found (SP, signal peptide; V, variable; C, conserved).

^bDifference in mean hydropathy indicates the difference in the bootstrap mean estimate of the Kyte-Doolittle hydropathy at the position, stratified by transmission status. A positive value indicates more hydrophobic residues in in utero mother-to-child transmission (IU); a negative value indicates more hydrophobic residues in the nontransmitters (NT).

^cThe most frequent amino acids are displayed using sequence logo, where the size of the letter is proportional to its frequency. The P values represent the raw (not multiple-hypothesis-corrected) correlation between hydropathy at the position and the transmission status.

^dThe most frequent amino acids in 757 HIV-1 subtype C sequences in the Los Alamos HIV database.