@article {6861, title = {White Matter Lesion Progression: Genome-Wide Search for Genetic Influences.}, journal = {Stroke}, volume = {46}, year = {2015}, month = {2015 Nov}, pages = {3048-57}, abstract = {

BACKGROUND AND PURPOSE: White matter lesion (WML) progression on magnetic resonance imaging is related to cognitive decline and stroke, but its determinants besides baseline WML burden are largely unknown. Here, we estimated heritability of WML progression, and sought common genetic variants associated with WML progression in elderly participants from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium.

METHODS: Heritability of WML progression was calculated in the Framingham Heart Study. The genome-wide association study included 7773 elderly participants from 10 cohorts. To assess the relative contribution of genetic factors to progression of WML, we compared in 7 cohorts risk models including demographics, vascular risk factors plus single-nucleotide polymorphisms that have been shown to be associated cross-sectionally with WML in the current and previous association studies.

RESULTS: A total of 1085 subjects showed WML progression. The heritability estimate for WML progression was low at 6.5\%, and no single-nucleotide polymorphisms achieved genome-wide significance (P<5{\texttimes}10(-8)). Four loci were suggestive (P<1{\texttimes}10(-5)) of an association with WML progression: 10q24.32 (rs10883817, P=1.46{\texttimes}10(-6)); 12q13.13 (rs4761974, P=8.71{\texttimes}10(-7)); 20p12.1 (rs6135309, P=3.69{\texttimes}10(-6)); and 4p15.31 (rs7664442, P=2.26{\texttimes}10(-6)). Variants that have been previously related to WML explained only 0.8\% to 11.7\% more of the variance in WML progression than age, vascular risk factors, and baseline WML burden.

CONCLUSIONS: Common genetic factors contribute little to the progression of age-related WML in middle-aged and older adults. Future research on determinants of WML progression should focus more on environmental, lifestyle, or host-related biological factors.

}, keywords = {Adult, Aged, Cohort Studies, Disease Progression, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Leukoencephalopathies, Male, Middle Aged, Prospective Studies, White Matter}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.115.009252}, author = {Hofer, Edith and Cavalieri, Margherita and Bis, Joshua C and DeCarli, Charles and Fornage, Myriam and Sigurdsson, Sigurdur and Srikanth, Velandai and Trompet, Stella and Verhaaren, Benjamin F J and Wolf, Christiane and Yang, Qiong and Adams, Hieab H H and Amouyel, Philippe and Beiser, Alexa and Buckley, Brendan M and Callisaya, Michele and Chauhan, Ganesh and de Craen, Anton J M and Dufouil, Carole and van Duijn, Cornelia M and Ford, Ian and Freudenberger, Paul and Gottesman, Rebecca F and Gudnason, Vilmundur and Heiss, Gerardo and Hofman, Albert and Lumley, Thomas and Martinez, Oliver and Mazoyer, Bernard and Moran, Chris and Niessen, Wiro J and Phan, Thanh and Psaty, Bruce M and Satizabal, Claudia L and Sattar, Naveed and Schilling, Sabrina and Shibata, Dean K and Slagboom, P Eline and Smith, Albert and Stott, David J and Taylor, Kent D and Thomson, Russell and T{\"o}glhofer, Anna M and Tzourio, Christophe and van Buchem, Mark and Wang, Jing and Westendorp, Rudi G J and Windham, B Gwen and Vernooij, Meike W and Zijdenbos, Alex and Beare, Richard and Debette, Stephanie and Ikram, M Arfan and Jukema, J Wouter and Launer, Lenore J and Longstreth, W T and Mosley, Thomas H and Seshadri, Sudha and Schmidt, Helena and Schmidt, Reinhold} } @article {9706, title = {Genetic Complexities of Cerebral Small Vessel Disease, Blood Pressure, and Dementia.}, journal = {JAMA Netw Open}, volume = {7}, year = {2024}, month = {2024 May 01}, pages = {e2412824}, abstract = {

IMPORTANCE: Vascular disease is a treatable contributor to dementia risk, but the role of specific markers remains unclear, making prevention strategies uncertain.

OBJECTIVE: To investigate the causal association between white matter hyperintensity (WMH) burden, clinical stroke, blood pressure (BP), and dementia risk, while accounting for potential epidemiologic biases.

DESIGN, SETTING, AND PARTICIPANTS: This study first examined the association of genetically determined WMH burden, stroke, and BP levels with Alzheimer disease (AD) in a 2-sample mendelian randomization (2SMR) framework. Second, using population-based studies (1979-2018) with prospective dementia surveillance, the genetic association of WMH, stroke, and BP with incident all-cause dementia was examined. Data analysis was performed from July 26, 2020, through July 24, 2022.

EXPOSURES: Genetically determined WMH burden and BP levels, as well as genetic liability to stroke derived from genome-wide association studies (GWASs) in European ancestry populations.

MAIN OUTCOMES AND MEASURES: The association of genetic instruments for WMH, stroke, and BP with dementia was studied using GWASs of AD (defined clinically and additionally meta-analyzed including both clinically diagnosed AD and AD defined based on parental history [AD-meta]) for 2SMR and incident all-cause dementia for longitudinal analyses.

RESULTS: In 2SMR (summary statistics-based) analyses using AD GWASs with up to 75 024 AD cases (mean [SD] age at AD onset, 75.5 [4.4] years; 56.9\% women), larger WMH burden showed evidence for a causal association with increased risk of AD (odds ratio [OR], 1.43; 95\% CI, 1.10-1.86; P = .007, per unit increase in WMH risk alleles) and AD-meta (OR, 1.19; 95\% CI, 1.06-1.34; P = .008), after accounting for pulse pressure for the former. Blood pressure traits showed evidence for a protective association with AD, with evidence for confounding by shared genetic instruments. In the longitudinal (individual-level data) analyses involving 10 699 incident all-cause dementia cases (mean [SD] age at dementia diagnosis, 74.4 [9.1] years; 55.4\% women), no significant association was observed between larger WMH burden and incident all-cause dementia (hazard ratio [HR], 1.02; 95\% CI, 1.00-1.04; P = .07). Although all exposures were associated with mortality, with the strongest association observed for systolic BP (HR, 1.04; 95\% CI, 1.03-1.06; P = 1.9 {\texttimes} 10-14), there was no evidence for selective survival bias during follow-up using illness-death models. In secondary analyses using polygenic scores, the association of genetic liability to stroke, but not genetically determined WMH, with dementia outcomes was attenuated after adjusting for interim stroke.

CONCLUSIONS: These findings suggest that WMH is a primary vascular factor associated with dementia risk, emphasizing its significance in preventive strategies for dementia. Future studies are warranted to examine whether this finding can be generalized to non-European populations.

}, keywords = {Aged, Aged, 80 and over, Alzheimer Disease, Blood Pressure, Cerebral Small Vessel Diseases, Dementia, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Male, Mendelian Randomization Analysis, Prospective Studies, Risk Factors, Stroke}, issn = {2574-3805}, doi = {10.1001/jamanetworkopen.2024.12824}, author = {Sargurupremraj, Muralidharan and Soumar{\'e}, A{\"\i}cha and Bis, Joshua C and Surakka, Ida and J{\"u}rgenson, Tuuli and Joly, Pierre and Knol, Maria J and Wang, Ruiqi and Yang, Qiong and Satizabal, Claudia L and Gudjonsson, Alexander and Mishra, Aniket and Bouteloup, Vincent and Phuah, Chia-Ling and van Duijn, Cornelia M and Cruchaga, Carlos and Dufouil, Carole and Chene, Genevi{\`e}ve and Lopez, Oscar L and Psaty, Bruce M and Tzourio, Christophe and Amouyel, Philippe and Adams, Hieab H and Jacqmin-Gadda, H{\'e}l{\`e}ne and Ikram, Mohammad Arfan and Gudnason, Vilmundur and Milani, Lili and Winsvold, Bendik S and Hveem, Kristian and Matthews, Paul M and Longstreth, W T and Seshadri, Sudha and Launer, Lenore J and Debette, Stephanie} } @article {9578, title = {Multi-omics and pathway analyses of genome-wide associations implicate regulation and immunity in verbal declarative memory performance.}, journal = {Alzheimers Res Ther}, volume = {16}, year = {2024}, month = {2024 Jan 20}, pages = {14}, abstract = {

BACKGROUND: Uncovering the functional relevance underlying verbal declarative memory (VDM) genome-wide association study (GWAS) results may facilitate the development of interventions to reduce age-related memory decline and dementia.

METHODS: We performed multi-omics and pathway enrichment analyses of paragraph (PAR-dr) and word list (WL-dr) delayed recall GWAS from 29,076 older non-demented individuals of European descent. We assessed the relationship between single-variant associations and expression quantitative trait loci (eQTLs) in 44 tissues and methylation quantitative trait loci (meQTLs) in the hippocampus. We determined the relationship between gene associations and transcript levels in 53 tissues, annotation as immune genes, and regulation by transcription factors (TFs) and microRNAs. To identify significant pathways, gene set enrichment was tested in each cohort and meta-analyzed across cohorts. Analyses of differential expression in brain tissues were conducted for pathway component genes.

RESULTS: The single-variant associations of VDM showed significant linkage disequilibrium (LD) with eQTLs across all tissues and meQTLs within the hippocampus. Stronger WL-dr gene associations correlated with reduced expression in four brain tissues, including the hippocampus. More robust PAR-dr and/or WL-dr gene associations were intricately linked with immunity and were influenced by 31 TFs and 2 microRNAs. Six pathways, including type I diabetes, exhibited significant associations with both PAR-dr and WL-dr. These pathways included fifteen MHC genes intricately linked to VDM performance, showing diverse expression patterns based on cognitive status in brain tissues.

CONCLUSIONS: VDM genetic associations influence expression regulation via eQTLs and meQTLs. The involvement of TFs, microRNAs, MHC genes, and immune-related pathways contributes to VDM performance in older individuals.

}, keywords = {Aged, Cognition, Genome-Wide Association Study, Humans, Memory, MicroRNAs, Multiomics, Polymorphism, Single Nucleotide}, issn = {1758-9193}, doi = {10.1186/s13195-023-01376-6}, author = {Mei, Hao and Simino, Jeannette and Li, Lianna and Jiang, Fan and Bis, Joshua C and Davies, Gail and Hill, W David and Xia, Charley and Gudnason, Vilmundur and Yang, Qiong and Lahti, Jari and Smith, Jennifer A and Kirin, Mirna and De Jager, Philip and Armstrong, Nicola J and Ghanbari, Mohsen and Kolcic, Ivana and Moran, Christopher and Teumer, Alexander and Sargurupremraj, Murali and Mahmud, Shamsed and Fornage, Myriam and Zhao, Wei and Satizabal, Claudia L and Polasek, Ozren and R{\"a}ikk{\"o}nen, Katri and Liewald, David C and Homuth, Georg and Callisaya, Michele and Mather, Karen A and Windham, B Gwen and Zemunik, Tatijana and Palotie, Aarno and Pattie, Alison and van der Auwera, Sandra and Thalamuthu, Anbupalam and Knopman, David S and Rudan, Igor and Starr, John M and Wittfeld, Katharina and Kochan, Nicole A and Griswold, Michael E and Vitart, Veronique and Brodaty, Henry and Gottesman, Rebecca and Cox, Simon R and Psaty, Bruce M and Boerwinkle, Eric and Chasman, Daniel I and Grodstein, Francine and Sachdev, Perminder S and Srikanth, Velandai and Hayward, Caroline and Wilson, James F and Eriksson, Johan G and Kardia, Sharon L R and Grabe, Hans J and Bennett, David A and Ikram, M Arfan and Deary, Ian J and van Duijn, Cornelia M and Launer, Lenore and Fitzpatrick, Annette L and Seshadri, Sudha and Bressler, Jan and Debette, Stephanie and Mosley, Thomas H} }