Recently S182 gene has been established as a candidate gene of chromosome 14-linked familial Alzheimer's desease. The putative S182 protein is thought to have seven-transmenbrane domein and specurated to be associated with the processing of amyloid beta protein.We screened the S182 gene mutation using RT-PCR restriction endonuclese fingerprinting (REF) SSCP analysis. RNA samples (extracted from brain, cultured fibroblast or peripheral lymphocytes) were obtained from five indipendent famlial Alzheimer's disease patients and 25 sporadic Alzheimre's desease patients. After the reversetranscription reaction, PCR was performed using the primer pair designed for covering S182 coding region. The 1702 bp PCR product was digested by restricted enzymes (DdeI, HinfI, HaeIII and HhaI, and DdeI + HinfI). After the denature step (95 o C, 5min), the digested products were 5' end-labeled with [γ- 3 2 P] ATP using T4 polynucleotidekinase. At the end of labeling reaction, stop/loading buffer were added to each labeling mixture. Electrophoresis of 12% MDE gel (sequence ge size) was performed at room temperature and in a cold room, and then gels were dried and subjected to autoradiography.No additional restricton sites and SSCP components were found in all analyzed patients. Our FAD families may link to other gene, and S182 gene mutations may be rare in sporadic Alzheimse's desease.