The NCRAD Family Study began in 1990 and continues to actively recruit and follow subjects. Families with two or more living, biologically related, members with early or late onset AD and related dementias are enrolled. Samples are obtained from affected family members and unaffected relatives (typically over age 60). Neuropathology has been completed in over 700 NCRAD Family Study participants and brain tissue is available for over 250 of those individuals.

The NCRAD Families sample set was genotyped at the Children’s Hospital of Philadelphia using the Illumina Infinium GSAMD-24v2-0_20024620_A1 BeadChip which captures genotype data on 759,993 genomic SNPs.