Oakes et al. found that as a negative regulator of ADAR2 activity, ADAR3, which is genetically amplified in ~ 2% of glioma, inhibits the binding of ADAR2 to the GRIA2 pre-mRNA transcript, preventing RNA editing [88], although the exact mechanism by which ADAR3 performs this function remains unclear. The gene discussed is ADARB2; the disease is glioma.