One of the obstacles to treatment of the human immunodeficiency virus is its high genetic variability. HIV can be divided into two major types, HIV type 1 (HIV-1) and HIV type 2 (HIV-2). HIV-1 is related to viruses found in chimpanzees and gorillas living in western Africa, while HIV-2 viruses are related to viruses found in sooty mangabeys. HIV-1 viruses may be further divided into groups. The HIV-1 group M viruses predominate and are responsible for the AIDS pandemic. Group M can be further subdivided into subtypes based on genetic sequence data. Some of the subtypes are known to be more virulent or are resistant to different medications. Likewise, HIV-2 viruses are thought to be less virulent and transmissible than HIV-1 M group viruses, although HIV-2 is known to cause AIDS. HIV-1 is the most common and pathogenic strain of the virus. Scientists divide HIV-1 into a major group (Group M) and two or more minor groups. Each group is believed to represent an independent transmission of SIV into humans (but subtypes within a group are not). Total 39 ORFs are found in all six possible reading frames (RFs) of HIV-1 complete genome sequence. But only few of them are functional.

The antibody is stable for at least 1 year from the date of receipt when stored at -20°C to -70°C. Reconstituted antibody can also be aliquotted and stored at 4°C for 1 month or at -20°C to -70°C in a manual defrost freezer for many months without detectable loss activity. Please avoid freeze-thaw cycles.