PROJECT SUMMARY This diversity supplement will support the career development for Lauren W. Yowelunh McLester-Davis, a member of the Oneida tribe and the only Native American graduate student at Tulane University. Given the paucity of Native Americans receiving doctoral degrees and NIH funding over the last decade, early targeted support, particularly for exceptionally qualified female Native American researchers in STEMM fields, is critical. This supplement will support one such candidate through a research program directly aligned with her own career goals and key professional interest areas by the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment – specifically the relation between disease detection, biomarkers and diversity, and ethnoracial factors related to Alzheimer's disease and related disorders (ADRD). The proposed supplement is aligned with the parent U24 (U24AG066528), that established the Telomere Research Network (TRN) to determine best practices for measurement of telomere length (TL) applicable to population-based studies and determine the ability of TL to serve a sentinel of the environmental exposome, psychosocial stress, and disease susceptibility across the life course. The proposed supplement will expand the aims of the parent grant with the following supplemental AIMS: Aim 1: To determine the relationship between TL and neuropsychological performance in African American and Native American middle-aged and older adults. It is hypothesized that the Rey Auditory Verbal Learning Test (RAVLT) and the Trail Making Test (TMT), which capture subtle cognitive changes associated with ADRD, will be significantly associated with peripheral blood TL within African and Native Americans. Aim 2a: To assess the correlation between TL in CSF and peripheral blood. It is hypothesized that TL measured in peripheral blood with be significantly correlated with TL measured from TL measured from white blood cells (WBCs) obtained from cerebrospinal fluid (CSF). Aim 2b: To assess the correlation of TL with DNA methylation- based age (DNAm age) from cells in CSF in middle-aged and older adults. It is hypothesized that TL will be associated with DNAm age and that CSF TL will demonstrate a stronger correlation with DNAm age in CSF WBCs than TL measured in peripheral WBC. Together the achievement of these Aims is expected to contribute to an enhanced understanding of relation between TL and with neuropsychological outcomes in minoritized populations and specific biomarkers of ADRD.