Document 0114
 DOCN  M9460114
 TI    Identification of three feline immunodeficiency virus (FIV) env gene
       subtypes and comparison of the FIV and human immunodeficiency virus type
       1 evolutionary patterns.
 DT    9404
 AU    Sodora DL; Shpaer EG; Kitchell BE; Dow SW; Hoover EA; Mullins JI;
       Department of Microbiology and Immunology, Stanford University; School
       of Medicine, California.
 SO    J Virol. 1994 Apr;68(4):2230-8. Unique Identifier : AIDSLINE +
 AB    Feline immunodeficiency virus (FIV) is a lentivirus associated with
       AIDS-like illnesses in cats. As such, FIV appears to be a feline analog
       of human immunodeficiency virus (HIV). A hallmark of HIV infection is
       the large degree of viral genetic diversity that can develop within an
       infected individual and the even greater and continually increasing
       level of diversity among virus isolates from different individuals. Our
       goal in this study was to determine patterns of FIV genetic diversity by
       focusing on a 684-nucleotide region encompassing variable regions V3,
       V4, and V5 of the FIV env gene in order to establish parallels and
       distinctions between FIV and HIV type 1 (HIV-1). Our data demonstrate
       that, like HIV-1, FIV can be separated into distinct envelope sequence
       subtypes (three are described here). Similar to that found for HIV-1,
       the pairwise sequence divergence within an FIV subtype ranged from 2.5
       to 15.0%, whereas that between subtypes ranged from 17.8 to 26.2%.
       However, the high number of synonymous nucleotide changes among FIV V3
       to V5 env sequences may also include a significant number of back
       mutations and suggests that the evolutionary distances among FIV
       subtypes are underestimated. Although only a few subtype B viruses were
       available for examination, the pattern of diversity between the FIV A
       and B subtypes was found to be significantly distinct; subtype B
       sequences had proportionally fewer mutations that changed amino acids,
       compared with silent changes, suggesting a more advanced state of
       adaptation to the host. No similar distinction was evident for HIV-1
       subtypes. The diversity of FIV genomes within individual infected cats
       was found to be as high as 3.7% yet twofold lower than that within
       HIV-1-infected people over a comparable region of the env gene. Despite
       these differences, significant parallels between patterns of FIV
       evolution and HIV-1 evolution exist, indicating that a wide array of
       potentially divergent virus challenges need to be considered in FIV
       vaccine and pathogenesis studies.
 DE    Adaptation, Biological  Amino Acid Sequence  Animal  Base Sequence  Cats
       Comparative Study  Evolution  Genes, env/*GENETICS
       HIV-1/CLASSIFICATION/*GENETICS  Immunodeficiency Virus,
       Feline/*CLASSIFICATION/*GENETICS/  ISOLATION & PURIF  Lentivirus
       Infections/EPIDEMIOLOGY/*MICROBIOLOGY  Molecular Sequence Data  Mutation
       North America/EPIDEMIOLOGY  Phylogeny  Polymerase Chain Reaction
       Sequence Analysis, DNA  Sequence Homology, Amino Acid  Support, Non-U.S.
       Gov't  Support, U.S. Gov't, P.H.S.  Variation (Genetics)  JOURNAL
       ARTICLE

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