Deltaretrovirus

The delta retroviruses are a genus within the family of retroviruses. They include, for example, the bovine leukemia virus and human pathogenic viruses HTLV -1 and HTLV -2. Close relatives of HTLV -1 and -2 are the simian ( monkey ) virus, STLV -1 and STLV -2. The delta retroviruses are transmitted from animal to animal and cause T- or B- cell leukemias. From the delta retroviruses no endogenous retrovirus variants are known.

Delta retroviruses were divided in 1998 into a genus due to phylogenetic relatedness. They have the accessory genes tax and rex that overlap each other.