For the first time in almost two decades, a new subtype of the Human Immunodeficiency Virus (HIV) that causes AIDS has been identified by genetic sequencing. The subtype belongs to the M group of HIV which is said to have resulted in most HIV infections. This was announced in November 2019.
Pharma major Abbott has reported that its team of scientists has identified the HIV-1 Group M, subtype L virus. The research marks the first time a new subtype of “Group M” HIV virus has been identified since guidelines for classifying new strains of HIV were established in 2000. Specimen CG-0018a-01, which has been sequenced to reveal that it is a hitherto unknown subtype of HIV, was collected in 2001 in the Democratic Republic of Congo (DRC) as part of an HIV prevention of mother to child transmission (PMTCT) study.
According to scientists, the three epidemiologically unlinked isolates or samples, CG-0018a-01 (recently identified), 83CD003, and 90CD121E12, may now be classified as HIV-1 group M, subtype L. This is the first new subtype classification identified since the nomenclature guidelines were established in 2009.
To determine whether an unusual virus is in fact a new HIV subtype, three cases must be discovered independently. The first two samples of this subtype—83CD003 and 90CD121E12—were discovered in DRC in 1983 and 1990. The third, collected in 2001, was difficult to sequence at that time because of the amount of virus in the sample and the existing technology.
Despite being the most recently sequenced subtype L strain, CG-0018a-01 branched basal to the two older strains, consistent with CG-0018a-01 being more closely related to the ancestral subtype L strain than the other two isolates. Therefore, the CG-0018a-01 sequence will be important for determining the origins and age of subtype L, the researchers noted.
To combat the HIV pandemic, scientists want to use the latest advancements in technology and resources to monitor the virus spread and growth. Sequencing of this strain is seen as a significant development in understanding, prevention and treatment of HIV because it is part of what has caused the most infections in humans.
The findings have been published in the Journal of Acquired Immune Deficiency Syndromes (JAIDS).