Protein conformation analyses have revealed that the V804M and V804L mutations modify the ATP-binding pockets of RET, facilitating ATP binding and conferring resistance to the multikinase inhibitor vandetanib, which is approved for the treatment of advanced MTC (Carlomagno et al. 2004, Wells et al. 2010). The gene discussed is RET; the disease is medullary thyroid gland carcinoma.