Browsing by Author "Widaman, Keith F."

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    Combined neuropathological pathways account for age-related risk of dementia
    (Wiley, 2018-07) Power, Melinda C.; Mormino, Elizabeth; Soldan, Anja; James, Bryan D.; Yu, Lei; Armstrong, Nicole M.; Bangen, Katherine J.; Delano-Wood, Lisa; Lamar, Melissa; Lim, Yen Ying; Nudelman, Kelly; Zahodne, Laura; Gross, Alden L.; Mungas, Dan; Widaman, Keith F.; Schneider, Julie; Radiology and Imaging Sciences, School of Medicine
    OBJECTIVE: Our objectives were to characterize the inter-relation of known dementia-related neuropathologies in one comprehensive model and quantify the extent to which accumulation of neuropathologies accounts for the association between age and dementia. METHODS: We used data from 1,362 autopsied participants of three community-based clinicopathological cohorts: the Religious Orders Study, the Rush Memory and Aging Project, and the Minority Aging Research Study. We estimated a series of structural equation models summarizing a priori hypothesized neuropathological pathways between age and dementia risk individually and collectively. RESULTS: At time of death (mean age, 89 years), 44% of our sample had a clinical dementia diagnosis. When considered individually, our vascular, amyloid/tau, neocortical Lewy body, and TAR DNA-binding protein 43 (TDP-43)/hippocampal sclerosis pathology pathways each accounted for a substantial proportion of the association between age and dementia. When considered collectively, the four pathways fully accounted for all variance in dementia risk previously attributable to age. Pathways involving amyloid/tau, neocortical Lewy bodies, and TDP-43/hippocampal sclerosis were interdependent, attributable to the importance of amyloid beta plaques in all three. The importance of the pathways varied, with the vascular pathway accounting for 32% of the association between age and dementia, wheraes the remaining three inter-related degenerative pathways together accounted for 68% (amyloid/tau, 24%; the Lewy body, 1%; and TDP-43/hippocampal sclerosis, 43%). INTERPRETATION: Age-related increases in dementia risk can be attributed to accumulation of multiple pathologies, each of which contributes to dementia risk. Multipronged approaches may be necessary if we are to develop effective therapies.
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    Sex differences in the genetic architecture of cognitive resilience to Alzheimer's disease
    (Oxford University Press, 2022) Eissman, Jaclyn M.; Dumitrescu, Logan; Mahoney, Emily R.; Smith, Alexandra N.; Mukherjee, Shubhabrata; Lee, Michael L.; Scollard, Phoebe; Choi, Seo Eun; Bush, William S.; Engelman, Corinne D.; Lu, Qiongshi; Fardo, David W.; Trittschuh, Emily H.; Mez, Jesse; Kaczorowski, Catherine C.; Hernandez Saucedo, Hector; Widaman, Keith F.; Buckley, Rachel F.; Properzi, Michael J.; Mormino, Elizabeth C.; Yang, Hyun Sik; Harrison, Theresa M.; Hedden, Trey; Nho, Kwangsik; Andrews, Shea J.; Tommet, Douglas; Hadad, Niran; Sanders, R. Elizabeth; Ruderfer, Douglas M.; Gifford, Katherine A.; Zhong, Xiaoyuan; Raghavan, Neha S.; Vardarajan, Badri N.; Alzheimer’s Disease Neuroimaging Initiative (ADNI); Alzheimer’s Disease Genetics Consortium (ADGC); A4 Study Team; Pericak-Vance, Margaret A.; Farrer, Lindsay A.; Wang, Li San; Cruchaga, Carlos; Schellenberg, Gerard D.; Cox, Nancy J.; Haines, Jonathan L.; Keene, C. Dirk; Saykin, Andrew J.; Larson, Eric B.; Sperling, Reisa A.; Mayeux, Richard; Cuccaro, Michael L.; Bennett, David A.; Schneider, Julie A.; Crane, Paul K.; Jefferson, Angela L.; Hohman, Timothy J.; Radiology and Imaging Sciences, School of Medicine
    Approximately 30% of elderly adults are cognitively unimpaired at time of death despite the presence of Alzheimer's disease neuropathology at autopsy. Studying individuals who are resilient to the cognitive consequences of Alzheimer's disease neuropathology may uncover novel therapeutic targets to treat Alzheimer's disease. It is well established that there are sex differences in response to Alzheimer's disease pathology, and growing evidence suggests that genetic factors may contribute to these differences. Taken together, we sought to elucidate sex-specific genetic drivers of resilience. We extended our recent large scale genomic analysis of resilience in which we harmonized cognitive data across four cohorts of cognitive ageing, in vivo amyloid PET across two cohorts, and autopsy measures of amyloid neuritic plaque burden across two cohorts. These data were leveraged to build robust, continuous resilience phenotypes. With these phenotypes, we performed sex-stratified [n (males) = 2093, n (females) = 2931] and sex-interaction [n (both sexes) = 5024] genome-wide association studies (GWAS), gene and pathway-based tests, and genetic correlation analyses to clarify the variants, genes and molecular pathways that relate to resilience in a sex-specific manner. Estimated among cognitively normal individuals of both sexes, resilience was 20-25% heritable, and when estimated in either sex among cognitively normal individuals, resilience was 15-44% heritable. In our GWAS, we identified a female-specific locus on chromosome 10 [rs827389, β (females) = 0.08, P (females) = 5.76 × 10-09, β (males) = -0.01, P(males) = 0.70, β (interaction) = 0.09, P (interaction) = 1.01 × 10-04] in which the minor allele was associated with higher resilience scores among females. This locus is located within chromatin loops that interact with promoters of genes involved in RNA processing, including GATA3. Finally, our genetic correlation analyses revealed shared genetic architecture between resilience phenotypes and other complex traits, including a female-specific association with frontotemporal dementia and male-specific associations with heart rate variability traits. We also observed opposing associations between sexes for multiple sclerosis, such that more resilient females had a lower genetic susceptibility to multiple sclerosis, and more resilient males had a higher genetic susceptibility to multiple sclerosis. Overall, we identified sex differences in the genetic architecture of resilience, identified a female-specific resilience locus and highlighted numerous sex-specific molecular pathways that may underly resilience to Alzheimer's disease pathology. This study illustrates the need to conduct sex-aware genomic analyses to identify novel targets that are unidentified in sex-agnostic models. Our findings support the theory that the most successful treatment for an individual with Alzheimer's disease may be personalized based on their biological sex and genetic context.
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    Sex-specific genetic predictors of memory, executive function, and language performance
    (Wiley, 2022) Eissman, Jaclyn M.; Smith, Alexandra N.; Mukherjee, Shubhabrata; Lee, Michael L.; Choi, Seo-Eun; Scollard, Phoebe; Trittschuh, Emily H.; Mez, Jesse B.; Bush, William S.; Engelman, Corinne D.; Lu, Qiongshi; Fardo, David W.; Widaman, Keith F.; Buckley, Rachel F.; Mormino, Elizabeth C.; Kunkle, Brian W.; Naj, Adam C.; Clark, Lindsay R.; Gifford, Katherine A.; Alzheimer’s Disease Neuroimaging Initiative (ADNI); Alzheimer’s Disease Genetics Consortium (ADGC); A4 Study Team; The Alzheimer’s Disease Sequencing Project (ADSP); Cuccaro, Michael L.; Cruchaga, Carlos; Pericak-Vance, Margaret A.; Farrer, Lindsay A.; Wang, Li-San; Schellenberg, Gerard D.; Haines, Jonathan L.; Jefferson, Angela L.; Johnson, Sterling C.; Kukull, Walter A.; Albert, Marilyn S.; Keene, C. Dirk; Saykin, Andrew J.; Larson, Eric B.; Sperling, Reisa A.; Mayeux, Richard; Thompson, Paul M.; Martin, Eden R.; Bennett, David A.; Barnes, Lisa L.; Schneider, Julie A.; Crane, Paul K.; Hohman, Timothy J.; Dumitrescu, Logan; Radiology and Imaging Sciences, School of Medicine
    Background: Alzheimer’s disease (AD) is more prevalent in women than men, and robust evidence shows sex differences in the biological response to the AD neuropathological cascade. However, there is a lack of large-scale genetic studies on sex-specific genetic predictors of AD-related cognitive outcomes. Thus, we sought to elucidate the sex-specific genetic etiology of memory, executive function, and language performance. Method: This study included six cohorts of cognitive aging (Nmales=7,267, Nfemales=9,518). We applied psychometric approaches to build harmonized memory, executive function, and language composite scores. Next, for all domains, we calculated slopes from the cognitive scores (two or more timepoints) with linear mixed effects models. Then we performed sex-stratified and sex-interaction GWAS on these phenotypes, covarying for baseline age and the first three genetic principal components. We meta-analyzed across cohorts with a fixed-effects model. Sensitivity analyses for all models restricted the sample to cognitively unimpaired individuals. Result: In addition to well-established associations with cognition at the APOE locus, we identified three genetic loci that showed sex-specific effects with cognition. A chromosome 16 locus (rs114106271), a splicing-quantitative trait locus for RP11-152O14.4 and LINC02180 in the testis (GTEx), associated with baseline memory performance in men (β=0.13, P=2.40×10-8; PInteraction=8.96×10-6; Figures 1-2) but not in women (β=-0.01, P=0.76). A chromosome 14 locus (rs34074573), an expression-quantitative trait locus (GTEx) for HOMEZ (a homeobox gene), and for BCL2L2 (a previously reported AD risk gene), associated with longitudinal memory performance in men (β=-0.01, P=4.15×10-8; PInteraction=5.83×10-7; Figures 3-4) but not in women (β=0.001, P=0.09). Finally, a chromosome 6 locus (rs9382966) associated with longitudinal language performance in men with near genome-wide significance (β=-0.004, P=6.29×10-8; PInteraction=2.01×10-4) but not in women (β=-0.0003, P=0.61). Conclusion: Our results highlight some key sex differences in the genetic architecture of cognitive outcomes. Findings further suggest that some sex-specific genetic predictors have domain-specific associations, providing an exciting opportunity to better understand the molecular basis of memory, executive function, and language through genomic analysis. Although our findings need to be replicated, our GWAS analyses highlight the contribution of sex-specific genetic predictors beyond the APOE locus in conferring risk for late-life cognitive decline.