In this computational study, we investigated the structural effects of a novel p53 mutation (G389E), identified in a patient with congenital adrenal hyperplasia, which is located within the extreme C-terminal domain (CTD) of p53, an unstructured, flexible region (residues 367–393) of major importance for the regulation of the protein. The gene discussed is TP53; the disease is congenital adrenal hyperplasia.