Capgras syndrome-a biochemical marker?
Two cased of Capgras syndrome are reported in which platelet monoamine oxidase (MAO) activity is singificantly less than that of 24 psychiatric controls and 39 nonpsychiatric controls. This is the first report of a consistent biochemical abnormality associated with the Capgras phenomenon. Additional evidence is discussed which suggests that psychiatric patients with  Capgras syndrome may belong to a discrete group of behavioral disorders characterized by reduced platelet MAO activity.
D000328:Adult; D001792:Blood Platelets / Q000201:enzymology*; D003702:Delusions / Q000097:blood / Q000201:enzymology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000097:blood*; D011618:Psychotic Disorders / Q000097:blood / Q000201:enzymology*; D013577:Syndrome
D008995:Monoamine Oxidase