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Item Correlation of plasma and neuroimaging biomarkers in Alzheimer’s disease(Wiley, 2022) Brickman, Adam M.; Manly, Jennifer J.; Honig, Lawrence S.; Sanchez, Danurys; Reyes-Dumeyer, Dolly; Lantigua, Rafael A.; Vonsattel, Jean Paul; Teich, Andrew F.; Kang, Min Suk; Dage, Jeffrey L.; Mayeux, Richard; Neurology, School of MedicineBlood-based phosphorylated tau (Ptau) 181 and 217 biomarkers are sensitive and specific for Alzheimer's disease. In this racial/ethnically diverse cohort study, participants were classified as biomarker positive (Ptau+) or negative (Ptau-) based on Ptau 181 and 217 concentrations and as cognitively impaired (Sym) or unimpaired (Asym). The four groups, Ptau-/Asym, Ptau+/Asym, Ptau-/Sym, and Ptau+/Sym, differed by age, APOE-4 allele frequency, total tau, neurofilament light chain, and cortical thickness measured by MRI. Our results add to increasing evidence that plasma Ptau 181 and 217 concentrations are valid Alzheimer's disease biomarkers in diverse populations.Item Evaluation of Plasma Biomarkers for A/T/N Classification of Alzheimer Disease Among Adults of Caribbean Hispanic Ethnicity(American Medical Association, 2023-04-03) Honig, Lawrence S.; Kang, Min Suk; Lee, Annie J.; Reyes-Dumeyer, Dolly; Piriz, Angel; Soriano, Belisa; Franco, Yahaira; Dominguez Coronado, Zoraida; Recio, Patricia; Rivera Mejía, Diones; Medrano, Martin; Lantigua, Rafael A.; Teich, Andrew F.; Dage, Jeffrey L.; Mayeux, Richard; Neurology, School of MedicineImportance: Cerebrospinal fluid (CSF) and plasma biomarkers can detect biological evidence of Alzheimer disease (AD), but their use in low-resource environments and among minority ethnic groups is limited. Objective: To assess validated plasma biomarkers for AD among adults of Caribbean Hispanic ethnicity. Design, setting, and participants: In this decision analytical modeling study, adults were recruited between January 1, 2018, and April 30, 2022, and underwent detailed clinical assessments and venipuncture. A subsample of participants also consented to lumbar puncture. Established CSF cut points were used to define AD biomarker-positive status, allowing determination of optimal cut points for plasma biomarkers in the same individuals. The performance of a panel of 6 plasma biomarkers was then assessed with respect to the entire group. Data analysis was performed in January 2023. Main outcomes and measures: Main outcomes were the association of plasma biomarkers amyloid-β 1-42 (Aβ42), amyloid-β 1-40 (Aβ40), total tau (T-tau), phosphorylated tau181 (P-tau181), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL) with AD diagnosis. These biomarkers allow assessment of amyloid (A), neurofibrillary degeneration (T), and neurodegeneration (N) aspects of AD. Statistical analyses performed included receiver operating characteristics, Pearson and Spearman correlations, t tests, and Wilcoxon rank-sum, chi-square, and Fisher exact tests. Exposures: Exposures included age, sex, education, country of residence, apolipoprotein-ε4 (APOE-ε4) allele number, serum creatinine, blood urea nitrogen, and body mass index. Results: This study included 746 adults. Participants had a mean (SD) age of 71.0 (7.8) years, 480 (64.3%) were women, and 154 (20.6%) met clinical criteria for AD. Associations were observed between CSF and plasma P-tau181 (r = .47 [95% CI, 0.32-0.60]), NfL (r = 0.57 [95% CI, 0.44-0.68]), and P-tau181/Aβ42 (r = 0.44 [95% CI, 0.29-0.58]). For AD defined by CSF biomarkers, plasma P-tau181 and P-tau181/Aβ42 provided biological evidence of AD. Among individuals judged to be clinically healthy without dementia, biomarker-positive status was determined by plasma P-tau181 for 133 (22.7%) and by plasma P-tau181/Aβ42 for 104 (17.7%). Among individuals with clinically diagnosed AD, 69 (45.4%) had plasma P-tau181 levels and 89 (58.9%) had P-tau181/Aβ42 levels that were inconsistent with AD. Individuals with biomarker-negative clinical AD status tended to have lower levels of education, were less likely to carry APOE-ε4 alleles, and had lower levels of GFAP and NfL than individuals with biomarker-positive clinical AD. Conclusions and relevance: In this cross-sectional study, plasma P-tau181 and P-tau181/Aβ42 measurements correctly classified Caribbean Hispanic individuals with and without AD. However, plasma biomarkers identified individuals without dementia with biological evidence of AD, and a portion of those with dementia whose AD biomarker profile was negative. These results suggest that plasma biomarkers can augment detection of preclinical AD among asymptomatic individuals and improve the specificity of AD diagnosis.Item New insights into the genetic etiology of Alzheimer's disease and related dementias(Springer Nature, 2022) Bellenguez, Céline; Küçükali, Fahri; Jansen, Iris E.; Kleineidam, Luca; Moreno-Grau, Sonia; Amin, Najaf; Naj, Adam C.; Campos-Martin, Rafael; Grenier-Boley, Benjamin; Andrade, Victor; Holmans, Peter A.; Boland, Anne; Damotte, Vincent; van der Lee, Sven J.; Costa, Marcos R.; Kuulasmaa, Teemu; Yang, Qiong; de Rojas, Itziar; Bis, Joshua C.; Yaqub, Amber; Prokic, Ivana; Chapuis, Julien; Ahmad, Shahzad; Giedraitis, Vilmantas; Aarsland, Dag; Garcia-Gonzalez, Pablo; Abdelnour, Carla; Alarcón-Martín, Emilio; Alcolea, Daniel; Alegret, Montserrat; Alvarez, Ignacio; Álvarez, Victoria; Armstrong, Nicola J.; Tsolaki, Anthoula; Antúnez, Carmen; Appollonio, Ildebrando; Arcaro, Marina; Archetti, Silvana; Arias Pastor, Alfonso; Arosio, Beatrice; Athanasiu, Lavinia; Bailly, Henri; Banaj, Nerisa; Baquero, Miquel; Barral, Sandra; Beiser, Alexa; Belén Pastor, Ana; Below, Jennifer E.; Benchek, Penelope; Benussi, Luisa; Berr, Claudine; Besse, Céline; Bessi, Valentina; Binetti, Giuliano; Bizarro, Alessandra; Blesa, Rafael; Boada, Mercè; Boerwinkle, Eric; Borroni, Barbara; Boschi, Silvia; Bossù, Paola; Bråthen, Geir; Bressler, Jan; Bresner, Catherine; Brodaty, Henry; Brookes, Keeley J.; Brusco, Luis Ignacio; Buiza-Rueda, Dolores; Bûrger, Katharina; Burholt, Vanessa; Bush, William S.; Calero, Miguel; Cantwell, Laura B.; Chene, Geneviève; Chung, Jaeyoon; Cuccaro, Michael L.; Carracedo, Ángel; Cecchetti, Roberta; Cervera-Carles, Laura; Charbonnier, Camille; Chen, Hung-Hsin; Chillotti, Caterina; Ciccone, Simona; Claassen, Jurgen A. H. R.; Clark, Christopher; Conti, Elisa; Corma-Gómez, Anaïs; Costantini, Emanuele; Custodero, Carlo; Daian, Delphine; Dalmasso, Maria Carolina; Daniele, Antonio; Dardiotis, Efthimios; Dartigues, Jean-François; de Deyn, Peter Paul; de Paiva Lopes, Katia; de Witte, Lot D.; Debette, Stéphanie; Deckert, Jürgen; Del Ser, Teodoro; Denning, Nicola; DeStefano, Anita; Dichgans, Martin; Diehl-Schmid, Janine; Diez-Fairen, Mónica; Dionigi Rossi, Paolo; Djurovic, Srdjan; Duron, Emmanuelle; Düzel, Emrah; Dufouil, Carole; Eiriksdottir, Gudny; Engelborghs, Sebastiaan; Escott-Price, Valentina; Espinosa, Ana; Ewers, Michael; Faber, Kelley M.; Fabrizio, Tagliavini; Fallgaard Nielsen, Sune; Fardo, David W.; Farotti, Lucia; Fenoglio, Chiara; Fernández-Fuertes, Marta; Ferrari, Raffaele; Ferreira, Catarina B.; Ferri, Evelyn; Fin, Bertrand; Fischer, Peter; Fladby, Tormod; Fließbach, Klaus; Fongang, Bernard; Fornage, Myriam; Fortea, Juan; Foroud, Tatiana M.; Fostinelli, Silvia; Fox, Nick C.; Franco-Macías, Emlio; Bullido, María J.; Frank-García, Ana; Froelich, Lutz; Fulton-Howard, Brian; Galimberti, Daniela; García-Alberca, Jose Maria; García-González, Pablo; Garcia-Madrona, Sebastian; Garcia-Ribas, Guillermo; Ghidoni, Roberta; Giegling, Ina; Giorgio, Giaccone; Goate, Alison M.; Goldhardt, Oliver; Gomez-Fonseca, Duber; González-Pérez, Antonio; Graff, Caroline; Grande, Giulia; Green, Emma; Grimmer, Timo; Grünblatt, Edna; Grunin, Michelle; Gudnason, Vilmundur; Guetta-Baranes, Tamar; Haapasalo, Annakaisa; Hadjigeorgiou, Georgios; Haines, Jonathan L.; Hamilton-Nelson, Kara L.; Hampel, Harald; Hanon, Olivier; Hardy, John; Hartmann, Annette M.; Hausner, Lucrezia; Harwood, Janet; Heilmann-Heimbach, Stefanie; Helisalmi, Seppo; Heneka, Michael T.; Hernández, Isabel; Herrmann, Martin J.; Hoffmann, Per; Holmes, Clive; Holstege, Henne; Huerto Vilas, Raquel; Hulsman, Marc; Humphrey, Jack; Jan Biessels, Geert; Jian, Xueqiu; Johansson, Charlotte; Jun, Gyungah R.; Kastumata, Yuriko; Kauwe, John; Kehoe, Patrick G.; Kilander, Lena; Kinhult Ståhlbom, Anne; Kivipelto, Miia; Koivisto, Anne; Kornhuber, Johannes; Kosmidis, Mary H.; Kukull, Walter A.; Kuksa, Pavel P.; Kunkle, Brian W.; Kuzma, Amanda B.; Lage, Carmen; Laukka, Erika J.; Launer, Lenore; Lauria, Alessandra; Lee, Chien-Yueh; Lehtisalo, Jenni; Lerch, Ondrej; Lleó, Alberto; Longstreth, William, Jr.; Lopez, Oscar; Lopez de Munain, Adolfo; Love, Seth; Löwemark, Malin; Luckcuck, Lauren; Lunetta, Kathryn L.; Ma, Yiyi; Macías, Juan; MacLeod, Catherine A.; Maier, Wolfgang; Mangialasche, Francesca; Spallazzi, Marco; Marquié, Marta; Marshall, Rachel; Martin, Eden R.; Martín Montes, Angel; Martínez Rodríguez, Carmen; Masullo, Carlo; Mayeux, Richard; Mead, Simon; Mecocci, Patrizia; Medina, Miguel; Meggy, Alun; Mehrabian, Shima; Mendoza, Silvia; Menéndez-González, Manuel; Mir, Pablo; Moebus, Susanne; Mol, Merel; Molina-Porcel, Laura; Montrreal, Laura; Morelli, Laura; Moreno, Fermin; Morgan, Kevin; Mosley, Thomas; Nöthen, Markus M.; Muchnik, Carolina; Mukherjee, Shubhabrata; Nacmias, Benedetta; Ngandu, Tiia; Nicolas, Gael; Nordestgaard, Børge G.; Olaso, Robert; Orellana, Adelina; Orsini, Michela; Ortega, Gemma; Padovani, Alessandro; Paolo, Caffarra; Papenberg, Goran; Parnetti, Lucilla; Pasquier, Florence; Pastor, Pau; Peloso, Gina; Pérez-Cordón, Alba; Pérez-Tur, Jordi; Pericard, Pierre; Peters, Oliver; Pijnenburg, Yolande A. L.; Pineda, Juan A.; Piñol-Ripoll, Gerard; Pisanu, Claudia; Polak, Thomas; Popp, Julius; Posthuma, Danielle; Priller, Josef; Puerta, Raquel; Quenez, Olivier; Quintela, Inés; Qvist Thomassen, Jesper; Rábano, Alberto; Rainero, Innocenzo; Rajabli, Farid; Ramakers, Inez; Real, Luis M.; Reinders, Marcel J. T.; Reitz, Christiane; Reyes-Dumeyer, Dolly; Ridge, Perry; Riedel-Heller, Steffi; Riederer, Peter; Roberto, Natalia; Rodriguez-Rodriguez, Eloy; Rongve, Arvid; Rosas Allende, Irene; Rosende-Roca, Maitée; Royo, Jose Luis; Rubino, Elisa; Rujescu, Dan; Sáez, María Eugenia; Sakka, Paraskevi; Saltvedt, Ingvild; Sanabria, Ángela; Sánchez-Arjona, María Bernal; Sanchez-Garcia, Florentino; Sánchez Juan, Pascual; Sánchez-Valle, Raquel; Sando, Sigrid B.; Sarnowski, Chloé; Satizabal, Claudia L.; Scamosci, Michela; Scarmeas, Nikolaos; Scarpini, Elio; Scheltens, Philip; Scherbaum, Norbert; Scherer, Martin; Schmid, Matthias; Schneider, Anja; Schott, Jonathan M.; Selbæk, Geir; Seripa, Davide; Serrano, Manuel; Sha, Jin; Shadrin, Alexey A.; Skrobot, Olivia; Slifer, Susan; Snijders, Gijsje J. L.; Soininen, Hilkka; Solfrizzi, Vincenzo; Solomon, Alina; Song, Yeunjoo; Sorbi, Sandro; Sotolongo-Grau, Oscar; Spalletta, Gianfranco; Spottke, Annika; Squassina, Alessio; Stordal, Eystein; Tartan, Juan Pablo; Tárraga, Lluís; Tesí, Niccolo; Thalamuthu, Anbupalam; Thomas, Tegos; Tosto, Giuseppe; Traykov, Latchezar; Tremolizzo, Lucio; Tybjærg-Hansen, Anne; Uitterlinden, Andre; Ullgren, Abbe; Ulstein, Ingun; Valero, Sergi; Valladares, Otto; Van Broeckhoven, Christine; Vance, Jeffery; Vardarajan, Badri N.; van der Lugt, Aad; Van Dongen, Jasper; van Rooij, Jeroen; van Swieten, John; Vandenberghe, Rik; Verhey, Frans; Vidal, Jean-Sébastien; Vogelgsang, Jonathan; Vyhnalek, Martin; Wagner, Michael; Wallon, David; Wang, Li-San; Wang, Ruiqi; Weinhold, Leonie; Wiltfang, Jens; Windle, Gill; Woods, Bob; Yannakoulia, Mary; Zare, Habil; Zhao, Yi; Zhang, Xiaoling; Zhu, Congcong; Zulaica, Miren; EADB; GR@ACE; DEGESCO; EADI; GERAD; Demgene; FinnGen; ADGC; CHARGE; Farrer, Lindsay A.; Psaty, Bruce M.; Ghanbari, Mohsen; Raj, Towfique; Sachdev, Perminder; Mather, Karen; Jessen, Frank; Ikram, M. Arfan; de Mendonça, Alexandre; Hort, Jakub; Tsolaki, Magda; Pericak-Vance, Margaret A.; Amouyel, Philippe; Williams, Julie; Frikke-Schmidt, Ruth; Clarimon, Jordi; Deleuze, Jean-François; Rossi, Giacomina; Seshadri, Sudha; Andreassen, Ole A.; Ingelsson, Martin; Hiltunen, Mikko; Sleegers, Kristel; Schellenberg, Gerard D.; van Duijn, Cornelia M.; Sims, Rebecca; van der Flier, Wiesje M.; Ruiz, Agustín; Ramirez, Alfredo; Lambert, Jean-Charles; Medical and Molecular Genetics, School of MedicineCharacterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele.Item Pattern and degree of individual brain atrophy predicts dementia onset in dominantly inherited Alzheimer's disease(Wiley, 2021-07-05) Keret, Ophir; Staffaroni, Adam M.; Ringman, John M.; Cobigo, Yann; Goh, Sheng-Yang M.; Wolf, Amy; Allen, Isabel Elaine; Salloway, Stephen; Chhatwal, Jasmeer; Brickman, Adam M.; Reyes-Dumeyer, Dolly; Bateman, Randal J.; Benzinger, Tammie L.S.; Morris, John C.; Ances, Beau M.; Joseph-Mathurin, Nelly; Perrin, Richard J.; Gordon, Brian A.; Levin, Johannes; Vöglein, Jonathan; Jucker, Mathias; la Fougère, Christian; Martins, Ralph N.; Sohrabi, Hamid R.; Taddei, Kevin; Villemagne, Victor L.; Schofield, Peter R.; Brooks, William S.; Fulham, Michael; Masters, Colin L.; Ghetti, Bernardino; Saykin, Andrew J.; Jack, Clifford R.; Graff-Radford, Neill R.; Weiner, Michael; Cash, David M.; Allegri, Ricardo F.; Chrem, Patricio; Yi, Su; Miller, Bruce L.; Rabinovici, Gil D.; Rosen, Howard J.; Pathology and Laboratory Medicine, School of MedicineIntroduction: Asymptomatic and mildly symptomatic dominantly inherited Alzheimer's disease mutation carriers (DIAD-MC) are ideal candidates for preventative treatment trials aimed at delaying or preventing dementia onset. Brain atrophy is an early feature of DIAD-MC and could help predict risk for dementia during trial enrollment. Methods: We created a dementia risk score by entering standardized gray-matter volumes from 231 DIAD-MC into a logistic regression to classify participants with and without dementia. The score's predictive utility was assessed using Cox models and receiver operating curves on a separate group of 65 DIAD-MC followed longitudinally. Results: Our risk score separated asymptomatic versus demented DIAD-MC with 96.4% (standard error = 0.02) and predicted conversion to dementia at next visit (hazard ratio = 1.32, 95% confidence interval [CI: 1.15, 1.49]) and within 2 years (area under the curve = 90.3%, 95% CI [82.3%-98.2%]) and improved prediction beyond established methods based on familial age of onset. Discussion: Individualized risk scores based on brain atrophy could be useful for establishing enrollment criteria and stratifying DIAD-MC participants for prevention trials.Item Polygenic risk score penetrance & recurrence risk in familial Alzheimer disease(Wiley, 2023) Qiao, Min; Lee, Annie J.; Reyes-Dumeyer, Dolly; Tosto, Giuseppe; Faber, Kelley; Goate, Alison; Renton, Alan; Chao, Michael; Boeve, Brad; Cruchaga, Carlos; Pericak-Vance, Margaret; Haines, Jonathan L.; Rosenberg, Roger; Tsuang, Debby; Sweet, Robert A.; Bennett, David A.; Wilson, Robert S.; Foroud, Tatiana; Mayeux, Richard; Vardarajan, Badri N.; Medical and Molecular Genetics, School of MedicineObjective: To compute penetrance and recurrence risk using a genome-wide PRS (including and excluding the APOE region) in families with Alzheimer's disease. Methods: Genotypes from the National Institute on Aging Late-Onset Alzheimer's Disease Family-Based Study and a study of familial Alzheimer's disease in Caribbean Hispanics were used to compute PRS with and without variants in the 2 MB region flanking APOE. PRS was calculated in using clumping/thresholding and Bayesian methods and was assessed for association with Alzheimer's disease and age at onset. Penetrance and recurrence risk for carriers in highest and lowest PRS quintiles were compared separately within APOE-ε4 carriers and non-carriers. Results: PRS excluding the APOE region was strongly associated with clinical and neuropathological diagnosis of AD. PRS association with AD was similar in participants who did not carry an APOE-ε4 allele (OR = 1.74 [1.53-1.91]) compared with APOE-ε4 carriers (1.53 [1.4-1.68]). Compared to the lowest quintile, the highest PRS quintile had a 10% higher penetrance at age 70 (p = 0.0006) and a 20% higher penetrance at age 80 (p < 10e-05). Stratifying by APOE-ε4 allele, PRS in the highest quintile was significantly more penetrant than the lowest quintile, both, within APOE-ε4 carriers (14.5% higher at age 80, p = 0.002) and non-carriers (26% higher at 80, p < 10e-05). Recurrence risk for siblings conferred by a co-sibling in the highest PRS quintile increased from 4% between the ages of 65-74 years to 39% at age 85 and older. Interpretation: PRS can be used to estimate penetrance and recurrence risk in familial Alzheimer's disease among carriers and non-carries of APOE-ε4.Item Risk of Alzheimer's Disease is Associated with Longitudinal Changes in Plasma Biomarkers in the Multiethnic Washington Heights, Inwood Columbia Aging Project Cohort(medRxiv, 2023-08-16) Gu, Yian; Honig, Lawrence S.; Kang, Min Suk; Bahl, Aanya; Sanchez, Danurys; Reyes-Dumeyer, Dolly; Manly, Jennifer J.; Lantigua, Rafael A.; Dage, Jeffrey L.; Brickman, Adam M.; Vardarajan, Badri N.; Mayeux, Richard; Neurology, School of MedicineIntroduction: Alzheimer's disease (AD) biomarkers can help differentiate cognitively unimpaired (CU) individuals from mild cognitive impairment (MCI) and dementia. The role of AD biomarkers in predicting cognitive impairment and AD needs examination. Methods: In 628 CU individuals from a multi-ethnic cohort, Aβ42, Aβ40, phosphorylated tau-181 (P-tau181), glial fibrillary acid protein (GFAP), and neurofilament light chain (NfL) were measured in plasma. Results: Higher baseline levels of P-tau181/Aβ42 ratio were associated with increased risk of incident dementia. A biomarker pattern (with elevated Aβ42/Aβ40 but low P-tau181/Aβ42) was associated with decreased dementia risk. Compared to CU, participants who developed MCI or dementia had a rapid decrease in the biomarker pattern reflecting AD-specific pathological change. Discussion: Elevated levels of AD biomarker P-tau181/Aβ42, by itself or combined with a low Aβ42/Aβ40 level, predicts clinically diagnosed AD. Individuals with a rapid change in these biomarkers may need close monitoring for the potential downward trajectory of cognition.Item The National Institute on Aging Late-Onset Alzheimer’s Disease Family Based Study: A resource for genetic discovery(Wiley, 2022) Reyes-Dumeyer, Dolly; Faber, Kelley; Vardarajan, Badri; Goate, Alison; Renton, Alan; Chao, Michael; Boeve, Brad; Cruchaga, Carlos; Pericak-Vance, Margaret; Haines, Jonathan L.; Rosenberg, Roger; Tsuang, Debby; Sweet, Robert A.; Bennett, David A.; Wilson, Robert S.; Foroud, Tatiana; Mayeux, Richard; Medical and Molecular Genetics, School of MedicineIntroduction: The National Institute on Aging Late-Onset Alzheimer's Disease Family Based Study (NIA-LOAD FBS) was established to study the genetic etiology of Alzheimer's disease (AD). Methods: Recruitment focused on families with two living affected siblings and a third first-degree relative similar in age with or without dementia. Uniform assessments were completed, DNA was obtained, as was neuropathology, when possible. Apolipoprotein E (APOE) genotypes, genome-wide single nucleotide polymorphism (SNP) arrays, and sequencing was completed in most families. Results: APOE genotype modified the age-at-onset in many large families. Novel variants and known variants associated with early- and late-onset AD and frontotemporal dementia were identified supporting an international effort to solve AD genetics. Discussion: The NIA-LOAD FBS is the largest collection of familial AD worldwide, and data or samples have been included in 123 publications addressing the genetic etiology of AD. Genetic heterogeneity and variability in the age-at-onset provides opportunities to investigate the complexity of familial AD.