Definitions of HIV-1 clade B nonamer sequence motifs.

<p>The different sequence motifs of the aligned HIV-1 clade B isolates were identified as shown with 20 sequences of a model nonamer position. The “Index” nonamer is the most prevalent sequence, present in 8 of the 20 isolates. The “Major” variant is the most common variant of the index (5/20). “Minor” variants are multiple different repeated sequences, each with incidences less than that or occasionally equal of the major variant. “Unique” variants are those represented by a single aligned sequence. “Nonatypes” (boxed) are the distinct variant sequences at a given nonamer position; in this example one of major, two of minor, and three of unique.