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
Jens Ritter Instruments made of heavy brass and completely lockable with a design meant to produce perfect conduction of the string oscillation. Ritter B1 String Attachment Each string attaches to the body separately which is meant to produce an absolutely independent tone development with sonic transparency. The optional Ritter BB1 Tremolo System operates with 4 radial miniature ball-bearings. This construction is meant to produce smooth action without the friction commonly found in classic tremolo systems. With a gear-driven spring tension adjuster, the BB1 can allow regulation of the spring tension without removing the instrument's rear cover plate. In addition to the numerous shapes