Transcription termination factor 2 (TTF2 also called Forkhead-box E1/FOXE1 ) is a transcription termination factor that couples ATP hydrolysis with the removal of RNA polymerase II from the DNA template. Single nucleotide polymorphism (SNP) within the 5'-UTR of TTF2 is associated with thyroid cancer risk.TTF2 is a member of the DEAD-like helicase superfamily, a diverse family of proteins involved in ATP-dependent RNA or DNA unwinding. This domain contains the ATP-binding region.