Identification of B and F human immunodeficiency virus subtypes in Chilean patients

Type I human immunodeficiency virus (HIV) is characterized by a great genetic variability. There are three groups of virus throughout the world: O, N and M. Group M is responsible for AIDS pandemic and is subdivided in 9 genetic subtypes. Most viral strains in South America are subtype B. To determine the frequency of HIV subtypes in Chilean patients. Genetic analysis of C2-V3-C3 region of the gene env in HIV strains coming from 77 Chilean subjects infected by different means. DNA heteroduplex mobility assay was used to determine HIV subtypes. Sixty eight cases were infected with subtype B (88.3%) and nine cases were infected with subtype F (11.7%). Subtype B is the predominant HIV in Chile, but subtype F is also present.