v-ETS erythroblastosis virus E26 oncogene homolog (ERG) is a 55 kDa, 486 amino acid transcriptional activator that contains one sterile alpha motif/pointed domain and one DNA binding ETS domain. Chromosomal translocations of ERG with TMPRSS2 (prostate cancer), SLC45A3 (prostate cancer), EWS (Ewing's sarcoma), FUS (leukemia), or ELF4 (leukemia) result in oncogenic proteins that contribute to the progression of those diseases.