Assessment of AD‐related plasma biomarkers in diverse ancestral populations.

Background: Plasma proteins as biomarkers for the differential diagnosis of AD from other similar neurodegenerative disorders, as well as the identification of preclinical AD, has recently been well supported across several large AD cohorts. However, these are composed primarily of individuals of non‐Hispanic European ancestry. Few studies have been performed in African‐American or Hispanic/Latinx AD populations to determine if plasma biomarkers are also useful in these populations. Given the differences in AD risk loci found across ancestries, the application of these biomarkers in diverse populations is not assured. Therefore, the aim of this study is to explore the utility of plasma biomarkers in AD, MCI and at‐risk family members from diverse ancestral backgrounds. Method: As part of ongoing initiatives to understand AD in individuals of diverse ancestry, we are measuring the plasma level of biomarkers in a cohort of more than 3,000 individuals. This includes: 999 African Americans (248 AD cases, 591 controls, 160 MCI), 581 Puerto Ricans (223 AD cases, 208 controls, 150 MCI), 1052 Puerto Ricans in families (411 AD cases, 413 controls, 228 MCI), 98 Cubans (23 AD cases, 39 controls, 36 MCI), and 117 Peruvians (33 AD cases, 75 controls, 9 MCI). We will also have data on autopsy confirmed European AD cases (37) and a cohort of Amish individuals (∼400 AD cases, ∼200 MCI, and ∼500 controls). Plasma proteins tested are Aβ42, Aβ40, total Tau, and p‐Tau181 using Simoa chemistry assays (Quanterix HD‐X). All measurements are performed in duplicate and data analysis performed using HD‐X Analyzer Software v1.6. Result: Measurement and analysis of biomarkers in this diverse dataset is currently underway and will be completed in a few months. These results will allow a direct comparison of biomarker analysis related to AD diagnosis between European, African, and Amerindian ancestries. Moreover, a family‐based design for over 1000 Puerto Rican individuals will be the first to identify potential heritable trends in biomarker levels. Conclusion: This study is critical to being to understand how plasma biomarkers for AD may vary across diverse ancestries and whether previous findings will be generalizable and useful for all individuals, regardless of ancestry. [ABSTRACT FROM AUTHOR]