Recombinant Forms of HIV Spreading Globally
Originally published by Reuters Health, May 7, 2002
NEW YORK (Reuters Health) — Newly identified recombinant forms of HIV-1 are being spread to diverse geographic regions, investigators report, which could have implications for the development of an AIDS vaccine.
Dr. Martine Peeters, of the Laboratoire Retrovirus in Montpellier, France, and colleagues characterized the genome sequences of isolates from an individual in Senegal and one in Mali. As they report in the Journal of Acquired Immune Deficiency Syndromes for April 15, the two isolates matched two others described in patients from Burkina Faso and Mali.
All four isolates comprised a mosaic genome structure that included fragments from HIV subtypes A, G, K, and J. They matched isolates previously described in patients from Burkina Faso, Mali, Ivory Coast, and Nigeria. On the basis of newly proposed nomenclature, the strains are designated CRF06-cpx. The strains have also been isolated from patients in France and Australia, indicating global spread.
Dr. Peeters' group notes the importance of seeking biological differences among subtypes and circulating recombinant forms and tracking their molecular epidemiology, "because recombination may introduce genetic and biological consequences that are far greater than those resulting from the steady accumulation of single mutations."
It remains to be seen how viral recombination will affect viral properties, such as host viral loads and drug resistance, the researchers suggest.
In another report in the same issue of the journal, Dr. Rafael N'jera, of the Instituto de Salud Carlos III in Madrid, Spain, and colleagues detail the characterization of the first reported recombinant to originate in Western Europe. Its genome is made up primarily of subtype G, with the extracellular portion subtype B's env. They propose the designation CRF14_BG.
The researchers also note that a parental nonrecombinant subtype strain has been isolated in the same area, implying that the recombinant virus was most likely generated locally in northwestern Spain or in Portugal. They postulate that sources of the G subtype viruses are fishermen infected by contact with prostitutes in sub-Saharan Africa or immigrants from former Portuguese colonies in Africa.
