Diagnostic method for Alzheimer's disease: examination of non-neural tissue

A method for screening for Alzheimer's Disease, comprising the steps of:

• obtaining a skin tissue biopsy sample from a patient suspected of having Alzheimer's Disease;
• performing an extraction suitable for extracting .beta.-amyloid protein, or a .beta.-amyloid precursor protein fragment comprising .beta.-amyloid protein, from the biopsy sample, and thereby obtaining an extract sample;
• optionally additionally solubilizing the .beta.-amyloid protein or the .beta.-amyloid precursor protein fragment comprising .beta.-amyloid protein present in the extract sample, and thereby obtaining a solution sample;
• contacting the extract sample or the solution sample with a quantity of antibodies specific to .beta.-amyloid protein or to a precursor protein fragment comprising .beta.-amyloid protein or to a peptide fragment of .beta.-amyloid protein of at least about eight amino acids sufficient to allow detection of said protein, protein fragment or peptide fragment;
• and
• detecting the specific binding reaction in the extract or solution sample between the antibodies and the .beta.-amyloid protein or the .beta.-amyloid precursor protein fragment comprising .beta.-amyloid protein wherein the presence of said binding reaction is indicative of Alzheimer's disease.