The purpose of the Alzheimer's Disease Genetics Study is to identify the genes that cause Alzheimer's disease. One of the ways in which risk-factor genes for late-onset Alzheimer's can be investigated is by identifying and collecting genetic material from families with multiple members diagnosed withthe disease that began at age 60 or older. Families will be evaluated for a medical diagnosis and other factors. If eligible, blood samples will be collected from participants to establish cell lines. If one of the identified family members is deceased, DNA will be extracted and stored from autopsy samples.

Qualifying families will have at least three members participating in the study: any two living family members diagnosed with Alzheimer's disease with an onset at age 60 or older and a third member with an age of onset greater than 50, if affected, and 60 or older, if unaffected. The goal is to recruit 1,000 families in 3 years. This research will include a collection of samples from ethnic/minority populations and other special populations, including African Americans, the Amish, Hispanics, Asian Americans, and Japanese-Americans.

Study sites are located all over the United States, and arrangements may be made for eligible families who do not live near a participating site. Local sites, including the NIA-sponsored Alzheimer's Disease Centers, will collect clinical and demographic data from these families, and the sites will send coded data (without identifiers) to the National Cell Repository for Alzheimer's Disease (NCRAD) at Indiana University. The biological samples and data from these families will be available to qualified researchers, who must sign an agreement to protect the privacy rights of participants in this study. An oversight committee and the cordinator of the NIA Alzheimer's Disease Genetics Study will review and monitor the process of family identification and enrollment, data collection, and the establishment of cell lines. This repository of DNA and cell lines was developed in hopes of discovering risk-factor genes that contribute to late-oset Alzheimer's.