Graph representation of SDL and invariant interactions in RT-T. 8 sub-graphs derived from our computational analysis, composed of 6, 7, 7, 7, 10, 13, 16 and 29 positions. A link between two position means that these two positions are at the surface of the protein and close in space. Moreover, a red link binds two SDL position. A green link binds a SDL position to an invariant position. Finally, a blue link binds two invariants positions. The numbers correspond to the HIV RT positions.