title: Assessment of a retrovirus sequence and other possible risk factors for the chronic fatigue syndrome in adults.
abstract: OBJECTIVE
  To assess whether the human T-lymphotropic virus type II (HTLV-II) gag gene sequence, a purportedly new laboratory marker of the chronic fatigue syndrome (CFS), and other possible risk factors for CFS, particularly those associated with retroviral transmission, are associated with well-characterized CFS.
  
  
  METHODS
  Two matched case-control studies.
  
  
  METHODS
  The metropolitan Atlanta area.
  
  
  METHODS
  Twenty-one patients with CFS who were identified by the Centers for Disease Control and Prevention CFS surveillance system; 21 CDC employee controls (laboratory study) and 42 neighborhood controls (risk-factor study) who were matched to patients by age, race, and gender.
  
  
  METHODS
  Peripheral blood lymphocytes and leukocytes were assayed for the HTLV-II gag gene sequence by polymerase chain reaction and specific Southern blot hybridization. Questionnaires elicited demographic and clinical information and a history of exposures associated with retrovirus transmission (for example, blood transfusions, sexual practices, intravenous drug use).
  
  
  RESULTS
  All patients were white and 86% were female. The median age at illness onset was 34 years (range, 16 to 51 years). The HTLV-II gag gene sequence was not identified in the blood of any patient or control under conditions in which the appropriate assay controls were positive. No statistical differences were observed between patients and controls in frequency of blood transfusions (10% compared with 7%), median number of sex partners before illness (3 compared with 3), bisexual or homosexual behavior (14% compared with 7%), intravenous drug use (0% compared with 0%), and other factors associated with retroviral infection.
  
  
  CONCLUSIONS
  The HTLV-II gag gene sequence was not a marker for CFS in this small study of well-defined patients, nor did other characteristics of the patients and controls support the hypothesis that a retrovirus, transmitted by usual modes, was a cause of CFS.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: A S
authors.initials: AS
authors.lastname: Khan
authors.forename: W M
authors.initials: WM
authors.lastname: Heneine
authors.forename: L E
authors.initials: LE
authors.lastname: Chapman
authors.forename: H E
authors.initials: HE
authors.lastname: Gary
authors.forename: T C
authors.initials: TC
authors.lastname: Woods
authors.forename: T M
authors.initials: TM
authors.lastname: Folks
authors.forename: L B
authors.initials: LB
authors.lastname: Schonberger
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015673:Fatigue Syndrome, Chronic / Q000209:etiology / Q000382:microbiology*; D005260:Female; D015750:Genes, gag; D015491:HTLV-II Infections / Q000175:diagnosis* / Q000382:microbiology; D015367:Human T-lymphotropic virus 2 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012307:Risk Factors