Adult polyglucosan body disease body disease do not have identified mutations in the "GBE1" gene. In these individuals, the cause of the disease is unknown. Along with evaluation of the symptoms and a neurological examination, a diagnosis can be made based on genetic testing. Whether or not a person is making sufficient amounts of functional glycogen branching enzyme can be determined by taking a skin biopsy and testing for activity of the enzyme. Examination of tissue biopsied from the sural nerve under a microscope can reveal the presence of polyglucosan bodies. There will also be white matter changes visible in a magnetic resonance imaging
Frank Ritter (professor) Psychology from the Carnegie-Mellon University. Ritter has received study fellowships from the United States Air Force Office of Scientific Research, and the European Science Foundation's program on Learning in Humans and Machines. Ritter directs The Applied Cognitive Science Lab at Penn State University. He studies cognitive modelling, cognitive architectures, human computer interaction, and learning. His research has been funded by the US Office of Navy Research, the United States Air Force Office of Scientific Research, DARPA, the Defence Evaluation and Research Agency (U.K.), and the U.K. Joint Council Initiative on Cognitive Science and Human Computer Interaction, as well as corporations