The NY-REN-21 tumor antigen was first identified by autologous antibodies in patients with renal-cell carcinoma. The function of NY-REN-21 has not been characterized yet, although the mouse homologue (ZFP38) was described as a transcription factor that binds to a specific bipartite DNA motif. NY-REN-21 is a multifinger protein of the C₂H₂ type, containing a conserved oligomerization domain (SCAN) in the N-terminal region and a predicted disordered central region. Mouse ZFP38 was described as unable to form homodimers and the recombinant NY-REN-21 does not bind to the DNA motif described for ZFP38. Our analyses show that the recombinant SCAN domain of NY-REN-21 can form homodimers. This domain also forms homodimers in the yeast two hybrid system. The central region of NY-REN-21 shows an aberrant mobility on SDS-PAGE and is intrinsically unstructured as reveled by circular dichroism, fluorescence and limited proteolysis. The full-length NY-REN-21 is a partially unfolded protein and its secondary structure content is affected by incubation with EDTA. The SCAN protein family comprises over 70 members in humans. SCAN is an oligomerization domain and its ability to form homo and heterodimers widens the number of gene targets that are regulated by this group of transcription factors. A large scale screening to identify NY-REN-21 interacting partners was performed using the yeast two-hybrid system with the SCAN domain as bait. This screen identified SCAND1, a SCAN family member, comprising a truncated SCAN box that lacks the third a-helix and the zinc finger region. The results described in this work indicate that NY-REN-21 can function either as a homodimer or as a heterodimer with SCAND1.