@article {6586, title = {Extreme deep white matter hyperintensity volumes are associated with African American race.}, journal = {Cerebrovasc Dis}, volume = {37}, year = {2014}, month = {2014}, pages = {244-50}, abstract = {

BACKGROUND: African Americans (AAs) have a higher prevalence of extreme ischemic white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) than do European Americans (EAs) based on the Cardiovascular Health Study (CHS) score. Ischemic white matter disease, limited to the deep white matter, may be biologically distinct from disease in other regions and may reflect a previously observed trend toward an increased risk of subcortical lacunar infarcts in AAs. We hypothesized that extreme deep WMH volume (DWMV) or periventricular volume (PV) may also have a higher prevalence in AAs. Thus, we studied extreme CHS scores and extreme DWMV and PV in a healthy population enriched for cardiovascular disease risk factors.

METHODS: We imaged the brains of 593 subjects who were first-degree relatives of probands with early onset coronary disease prior to 60 years of age. WMHs were manually delineated on 3-tesla cranial MRI by a trained radiology reader; the location and volume of lesions were characterized using automated software. DWMV and PV were measured directly with automated software, and the CHS score was determined by a neuroradiologist. Volumes were characterized as being in the upper 25\% versus lower 75\% of total lesion volume. Volumes in the upper versus the remaining quartiles were examined for AA versus EA race using multiple logistic regression (generalized estimating equations adjusted for family relatedness) and adjusted for major vascular disease risk factors including age >=55 years versus <55, sex, current smoking, obesity, hypertension, diabetes and low-density lipoprotein >160 mg/dl.

RESULTS: Participants were 58\% women and 37\% AAs, with a mean age of 51.5 {\textpm} 11.0 years (range, 29-74 years). AAs had significantly higher odds of having extreme DWMVs (odds ratio, OR, 1.8; 95\% confidence interval, CI, 1.2-2.9; p = 0.0076) independently of age, sex, hypertension and all other risk factors. AAs also had significantly higher odds of having extreme CHS scores >=3 (OR, 1.3; 95\% CI, 1.1-3.6; p = 0.025). Extreme PV was not significantly associated with AA race (OR, 1.3; 95\% CI, 0.81-2.1; p = 0.26).

CONCLUSIONS: AAs from families with early-onset cardiovascular disease are more likely to have extreme DWMVs (a subclinical form of cerebrovascular disease) and an extreme CHS score, but not extreme PV, independently of age and other cardiovascular disease risk factors. These findings suggest that this AA population is at an increased risk for DWMV and may be at an increased risk for future subcortical stroke. Longitudinal studies are required to see if DWMV is predictive of symptomatic subcortical strokes in this population.

}, keywords = {Adult, African Americans, Age Factors, Aged, Cerebrovascular Disorders, European Continental Ancestry Group, Female, Humans, Hypertension, Magnetic Resonance Imaging, Male, Middle Aged, Prevalence, Risk Factors, White Matter}, issn = {1421-9786}, doi = {10.1159/000358117}, author = {Nyquist, Paul A and Bilgel, Murat S and Gottesman, Rebecca and Yanek, Lisa R and Moy, Taryn F and Becker, Lewis C and Cuzzocreo, Jennifer and Prince, Jerry and Yousem, David M and Becker, Diane M and Kral, Brian G and Vaidya, Dhananjay} } @article {6812, title = {Meta-Analysis of Genome-Wide Association Studies Identifies Genetic Risk Factors for Stroke in African Americans.}, journal = {Stroke}, volume = {46}, year = {2015}, month = {2015 Aug}, pages = {2063-8}, abstract = {

BACKGROUND AND PURPOSE: The majority of genome-wide association studies (GWAS) of stroke have focused on European-ancestry populations; however, none has been conducted in African Americans, despite the disproportionately high burden of stroke in this population. The Consortium of Minority Population Genome-Wide Association Studies of Stroke (COMPASS) was established to identify stroke susceptibility loci in minority populations.

METHODS: Using METAL, we conducted meta-analyses of GWAS in 14 746 African Americans (1365 ischemic and 1592 total stroke cases) from COMPASS, and tested genetic variants with P<10(-6) for validation in METASTROKE, a consortium of ischemic stroke genetic studies in European-ancestry populations. We also evaluated stroke loci previously identified in European-ancestry populations.

RESULTS: The 15q21.3 locus linked with lipid levels and hypertension was associated with total stroke (rs4471613; P=3.9{\texttimes}10(-8)) in African Americans. Nominal associations (P<10(-6)) for total or ischemic stroke were observed for 18 variants in or near genes implicated in cell cycle/mRNA presplicing (PTPRG, CDC5L), platelet function (HPS4), blood-brain barrier permeability (CLDN17), immune response (ELTD1, WDFY4, and IL1F10-IL1RN), and histone modification (HDAC9). Two of these loci achieved nominal significance in METASTROKE: 5q35.2 (P=0.03), and 1p31.1 (P=0.018). Four of 7 previously reported ischemic stroke loci (PITX2, HDAC9, CDKN2A/CDKN2B, and ZFHX3) were nominally associated (P<0.05) with stroke in COMPASS.

CONCLUSIONS: We identified a novel genetic variant associated with total stroke in African Americans and found that ischemic stroke loci identified in European-ancestry populations may also be relevant for African Americans. Our findings support investigation of diverse populations to identify and characterize genetic risk factors, and the importance of shared genetic risk across populations.

}, keywords = {African Americans, Case-Control Studies, Cohort Studies, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Polymorphism, Single Nucleotide, Risk Factors, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.115.009044}, author = {Carty, Cara L and Keene, Keith L and Cheng, Yu-Ching and Meschia, James F and Chen, Wei-Min and Nalls, Mike and Bis, Joshua C and Kittner, Steven J and Rich, Stephen S and Tajuddin, Salman and Zonderman, Alan B and Evans, Michele K and Langefeld, Carl D and Gottesman, Rebecca and Mosley, Thomas H and Shahar, Eyal and Woo, Daniel and Yaffe, Kristine and Liu, Yongmei and Sale, Mich{\`e}le M and Dichgans, Martin and Malik, Rainer and Longstreth, W T and Mitchell, Braxton D and Psaty, Bruce M and Kooperberg, Charles and Reiner, Alexander and Worrall, Bradford B and Fornage, Myriam} } @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} }