       Document 3279
 DOCN  M94A3279
 TI    Darwinian evolution operates on the V3 region of HIV within a single
       host.
 DT    9412
 AU    Yamaguchi Y; Gojobori T; National Institute of Genetics, Shizuoka,
       Japan.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):112 (abstract no. PA0066). Unique
       Identifier : AIDSLINE ICA10/94369296
 AB    OBJECTIVE: The purpose of this study is to elucidate the mechanisms of
       molecular evolution of the third variable envelope (V3) region for HIV
       within a single host. In particular, we intend to examine the patterns
       of nucleotide substitutions in this region to see whether positive
       selection is operating on the V3 region. METHODS: We constructed
       phylogenetic trees by use of nucleotide sequences of HIV within a host.
       We examined whether nonsynonymous (amino acid altering) substitutions
       are occurring with a frequency higher than synonymous (silent)
       substitutions. RESULTS: Our statistical test showed that for the V3
       region, the average number of nonsynonymous substitutions was
       significantly larger than that of synonymous substitutions. It suggests
       that Darwinian evolution is operating on the V3 region. For the entire
       env gene, however, the number of synonymous substitutions was larger
       than that of nonsynonymous substitutions, implying that neutral
       evolution is occurring in the entire env gene. DISCUSSION AND
       CONCLUSIONS: Our observations indicate that Darwinian evolution may be
       operating on the V3 region for HIV, although neutral evolution is
       occuring in the entire env gene.
 DE    *Evolution  *Genes, env  Human  HIV/*GENETICS/ISOLATION & PURIF  HIV
       Envelope Protein gp120/*GENETICS  HIV Infections/MICROBIOLOGY  Peptide
       Fragments/*GENETICS  Phylogeny  Variation (Genetics)  MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

