Lentiviruses have the protein Vif (virion infectivity factor) whose well known role is to lead to degradation of the host cell APOBEC 3 (A 3) proteins, but they are cytosine deaminases that deaminate cyrosine in the viral –DNA strand, thus causing G-A hypermutations in the viral + strand DNA if the Vif protein is defective or missing.
Lentiveirur hafa próteinið Vif (virion infectivity factor) sem hefur það velþekkta hlutverk að leiða til niðurbrots APOBEC 3 (A 3) próteina hýsilfrumna, en þau eru cytósín afamínasar sem valda miklum fjölda G-A stökkbreytinga í + DNA veirunnar ef Vif prótein er ekki virkt.