title: Brazilian HTLV type 2a strains from intravenous drug users (IDUs) appear to have originated from two sources: Brazilian Amerindians and European/North American IDUs.
abstract: In Brazil, HTLV-2 has been detected in blood donors, in intravenous drug users (IDUs) from urban areas, and in Amerindians living in the Amazon basin. Of the three main HTLV-2 subtypes (2a, 2b, and 2d) only subtype 2a has been detected in Brazil. However, a molecular variant of subtype 2a (also called HTLV-2c) characterized by an extended Tax protein has been isolated from Brazilian blood donors, IDUs, and Indians. Here, we analyzed HTLV-2 isolates from 10 IDUs and a Chilean woman living in Salvador, Bahia, Brazil. Sequencing of env, pX, and long terminal repeat (LTR) genes demonstrated that 10 of the isolates are related to the Brazilian subtype 2a molecular variant described previously. We show that most HTLV-2a Brazilian strains comprise a phylogenetic group harboring a considerable degree of diversity within the env region but not within the LTR region. Interestingly, we demonstrated for the first time in Brazil the presence of a subtype 2a in IDUs that is closely related to the prototype Mo but distinct from the Brazilian 2a molecular variant.
authors.affiliation: Advanced Public Health Laboratory, Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Salvador, Bahia, Brazil.
authors.forename: Luiz C J
authors.initials: LC
authors.lastname: Alcantara
authors.forename: Nice
authors.initials: N
authors.lastname: Shindo
authors.forename: Sonia
authors.initials: S
authors.lastname: Van Dooren
authors.forename: Marco
authors.initials: M
authors.lastname: Salemi
authors.forename: Maria C R
authors.initials: MC
authors.lastname: Costa
authors.forename: Simone
authors.initials: S
authors.lastname: Kashima
authors.forename: Dimas T
authors.initials: DT
authors.lastname: Covas
authors.forename: Anne-Mieke
authors.initials: AM
authors.lastname: Vandamme
authors.forename: Bernardo
authors.initials: B
authors.lastname: Galvão-Castro
mesh_terms: D000328:Adult; D001938:Brazil / Q000453:epidemiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D015686:Gene Products, env / Q000737:chemistry / Q000235:genetics; D015491:HTLV-II Infections / Q000453:epidemiology* / Q000821:virology; D015367:Human T-lymphotropic virus 2 / Q000145:classification* / Q000235:genetics; D006801:Humans; D007199:Indians, South American; D008297:Male; D008969:Molecular Sequence Data; D009656:North America / Q000453:epidemiology; D010802:Phylogeny; D015682:Retroviridae Proteins, Oncogenic / Q000737:chemistry / Q000235:genetics; D017422:Sequence Analysis, DNA; D015819:Substance Abuse, Intravenous / Q000150:complications*; D020079:Terminal Repeat Sequences / Q000235:genetics
chemical_list: D015686:Gene Products, env; D015682:Retroviridae Proteins, Oncogenic