Genetic Data Identify Dual‐enrolled Participants in Alzheimer's Disease and Related Dementia (ADRD) Studies

Abstract

AbstractBackgroundIt is not unusual for Alzheimer’s Disease (AD) Research Center (ADRC) participants to enroll in additional studies such as the AD Neuroimaging Initiative (ADNI). In such cases, shared access to neuropathologic biospecimens is important to both studies, but dual‐enrollment status is not always known to acting ADRC personnel, and currently there is no centralized method to track dual enrollment. For this study, we aimed to identify individuals enrolled in ADNI and an ADRC, and identify those with autopsy data available through an ADRC but not ADNI.MethodGWAS data were obtained for ADRC participants (N=22,935) through the AD Genetics Consortium (ADGC) and for ADNI participants (N=2,048) through the Laboratory of NeuroImaging (LONI); data were compared in PLINK v1.9 by identity‐by‐descent (IBD). ADRC/ADNI matches were filtered for pi‐hat > 0.8. Genotype data from a custom‐96 SNP microarray for ADRC and ADNI samples banked at the National Centralized Repository for Alzheimer’s Disease and Related Dementias (NCRAD) were also compared to identify additional matches. Year of birth, sex, race, and ethnicity were compared within matches. Participant IDs from matches were reviewed for autopsy data available through the National Alzheimer’s Coordinating Center (NACC) Uniform Data Set (UDS) and from ADNI, to identify participants with autopsy data available through NACC but not ADNI. We generated counts for matches that had year of death, and among those, how many had neuropathology variables.ResultWe identified 364 pairs with matched genetic (pi‐hat>0.99) and available demographic data from GWAS data, and another 52 from NCRAD genotype data. Of these, 143 matched ADRC participants had a year of death. 98 of the 143 had autopsy variables in the NACC UDS. 44 of these 98 were included in the ADNI autopsy data set (2018 version) or pending integration by the ADNI Neuropathology Core (NPC). Thus, 54 ADRC brain donors could be reported to the ADRCs as dually‐enrolled in ADNI, providing the involved ADRCs the opportunity to share these biospecimens with the ADNI NPC.ConclusionThis case study illustrates how identification of dually‐enrolled participants represents a unique opportunity to leverage data collected through multiple studies to enhance AD research.