The “Eye-of-the-Tiger” Sign Is Not Pathognomonic of the PANK2 Mutation

Abstract

and mental retardation was evaluated for a 3-year history of gait difficulties, cognitive decline, and seizures.HerbrainMRimages(Figure, A-C) showed the classic eye-of-thetigersign,butgenetictestingformutationsinthePANK2genewasnegative. All 7 coding exons of the PANK2 gene were amplified by means of polymerase chain reaction and then cycle sequenced in both forward and reverse directions from genomic DNA. PATIENT 2 A 31-year-old man with a history of lifelongmildlearningdisabilitywas evaluated for a 14-year history of ataxia and a 4-year history of cognitive decline. Brain MR imaging showed the eye-of-the-tiger sign (Figure,D-F).Genetictestingforthe PANK2 mutation and for the mutation in the ferritin light-chain proteinseeninneuroferritinopathywere negative.