encode accessory proteins (p12, p13/p30), the Rex post-transcriptional regulator (ORF III) and the Tax protein (ORF IV).

In addition to the essential viral genes gag, prt, pol, and env, HTLV-1 encodes regulatory and accessory genes for the pX region open reading frames (ORFs), which are located between the env gene and the 3’ portion of the viral genome.

HTLV-1 contains a linear, dimeric, ssRNA(+) genome of 8,507nt , with a 5’-cap and a 3’poly-A tail