THE NACP SYNUCLEIN GENE - CHROMOSOMAL ASSIGNMENT AND SCREENING FOR ALTERATIONS IN ALZHEIMER-DISEASE/

The major component of the vascular and plaque amyloid deposits in Alz heimer disease is the amyloid beta peptide (A beta). A second intrinsi c component of amyloid, the NAC (non-A beta component of amyloid) pept ide, has recently been identified, and its precursor protein was named NACP. A computer homology search allowed us to establish that the hum an NACP gene was homologous to the rat synuclein gene. We mapped the N ACP/synuclein gene to chromosome 4 and cloned three alternatively spli ced transcripts in lymphocytes derived from a normal subject. We analy zed by RT-PCR and direct sequencing the entire coding region of the NA CP/synuclein gene in a group of patients with familial early onset Alz heimer disease. No mutation was found in 26 unrelated patients. Furthe r studies are required to investigate the implication of the NACP/synu clein gene in Alzheimer disease. (C) 1995 Academic Press, Inc.