Background: Annotation of target genes of non-coding GWAS loci remains a challenge since 1) regulatory elements identified by GWAS can be metabases away from its actual target, 2) one regulatory element can target multiple genes, and 3) multiple regulatory elements can target one gene. AD GWAS in populations with different ancestries have identified different loci, suggesting ancestry-specific genetic risks. To understand the connection between associated loci (potential regulatory elements) and their target genes, we conducted Hi-C analysis in frontal cortex of African American (AA) and Non-Hispanic Whites (NHW) AD patients to map chromatin loops, which often represent enhancer-promoter (EP) interactions.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Background: The effect size of APOE4 varies across genetic ancestries with African (AFR) local ancestry conferring a lower risk when compared to other ancestries. Recently, we identified a strong effect of the A allele of rs10423769 (with a minor allele frequency of 0.12 in AFR and 0.
View Article and Find Full Text PDFBackground: Alzheimer's Disease (AD) and Age-Related Macular Degeneration (AMD) are two age related neurodegenerative diseases that share multiple characteristics, including deposition of amyloid beta. In AD, amyloid plaque accumulation contributes to neurological dysfunction, while in AMD amyloid is a component of the hallmark retinal drusen complexes that lead to degeneration of central vision. Both diseases have significant and opposite risk due to the APOE e4 and e2 alleles.
View Article and Find Full Text PDFBackground: While Alzheimer's disease and dementia prevalence increase with age, some older adults retain cognitive performance equal to those in mid-life. One group, referred to as SuperAgers (SA), are ≥ 80 years old and demonstrate episodic memory function at or above the level expected for a middle-aged adult. Genetic studies of SA may reveal heritable factors that promote superior cognition in older adults.
View Article and Find Full Text PDFBackground: Non-Hispanic White APOE4 carriers have a higher risk of developing AD compared to African American APOE4 carriers. The local ancestry (LA) surrounding the APOE region was previously shown to be the primary factor in this risk difference. APOE4 carriers of European LA (ELA) have been found to have higher APOE4 expression and chromatin accessibility compared to African LA (ALA).
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