A change in the regulation of the beta-amyloid precursor protein (beta APP) gene may be a factor for Alzheimer's disease (AD). We have screened a rhesus monkey genomic library and pulled out a approximately 17 kb genomic DNA region which contains the 5'-flanking region (promoter), first exon and intron of the beta APP gene of the Rhesus monkey (rh beta APP). We have partially characterized the genomic clone by selective restriction enzyme digestion followed by Southern blotting against the beta APP gene-specific DNA probes. The identity and authenticity of the different bands of the clone were also confirmed by Southern blot analysis of the rhesus monkey genomic DNA. Functional identification of the genomic fragment was determined by a promoter assay using the chloramphenicol acetyltransferase (CAT) enzyme as a reported gene. Our results showed that a 1.2 kb fragment from the 5'-flanking region of the rh beta APP gene possessed strong promoter activity. The isolation of this genomic clone will enable characterization of the structure and function of the promoter of the rh beta APP gene. Our initial results indicate a high degree of homology between the structure of the rhesus monkey and human beta APP promoter.