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Background: High-density lipoprotein cholesterol (HDL-C) exerts many anti-atherogenic properties including its role in reverse cholesterol transport (RCT). Scavenger receptor class B member 1 (SCARB1) plays a key role in RCT by selective uptake of HDL cholesteryl esters. We aimed to explore the genetic contribution of SCARB1 to affecting lipid levels in African Blacks from Nigeria. Methods: We resequenced 13 exons and exon-intron boundaries of SCARB1 in 95 individuals with extreme HDL-C levels using Sanger method. Then, we genotyped 147 selected variants (78 sequence variants, 69 HapMap tagSNPs, and 2 previously reported relevant variants) in the entire sample of 788 African Blacks using either the iPLEX Gold or TaqMan methods. A total of 137 successfully genotyped variants were further evaluated for association with major lipid traits. Results: The initial gene-based analysis demonstrated evidence of association with HDL-C and apolipoprotein A-I (ApoA-I). The follow-up single-site analysis revealed nominal evidence of novel associations of nine common variants with HDL-C and/or ApoA-I (P < 0.05). The strongest association was between rs11057851 and HDL-C (P = 0.0043), which remained significant after controlling for multiple testing using false discovery rate. Rare variant association testing revealed a group of 23 rare variants (frequencies ≤1 %) associated with HDL-C (P = 0.0478). Haplotype analysis identified four SCARB1 regions associated with HDL-C (global P < 0.05). Conclusions: To our knowledge, this is the first report of a comprehensive association study of SCARB1 variations with lipid traits in an African Black population. Our results showed the consistent association of SCARB1 variants with HDL-C across various association analyses, supporting the role of SCARB1 in lipoprotein-lipid regulatory mechanism. [ABSTRACT FROM AUTHOR]

The article discusses the research that investigates the common and low-frequency allele frequency variants of human scavenger receptor class B type I on plasma lipid traits. It states that three variants associated with apoB remained significant after false discovery rate. It mentions that the most signification association was detected between rs4765615 and apoB, while rs11057844 showed strongest link with high-density lipoprotein cholesterol (HDL-C).

Systemic lupus erythematosus (SLE) is a clinically heterogeneous, systemic autoimmune disease characterized by autoantibody formation. Previously published genome-wide association studies (GWAS) have investigated SLE as a single phenotype. Therefore, we conducted a GWAS to identify genetic factors associated with anti–dsDNA autoantibody production, a SLE–related autoantibody with diagnostic and clinical importance. Using two independent datasets, over 400,000 single nucleotide polymorphisms (SNPs) were studied in a total of 1,717 SLE cases and 4,813 healthy controls. Anti–dsDNA autoantibody positive (anti–dsDNA +, n = 811) and anti–dsDNA autoantibody negative (anti–dsDNA –, n = 906) SLE cases were compared to healthy controls and to each other to identify SNPs associated specifically with these SLE subtypes. SNPs in the previously identified SLE susceptibility loci STAT4, IRF5, ITGAM, and the major histocompatibility complex were strongly associated with anti–dsDNA + SLE. Far fewer and weaker associations were observed for anti–dsDNA – SLE. For example, rs7574865 in STAT4 had an OR for anti–dsDNA + SLE of 1.77 (95% CI 1.57–1.99, p = 2.0E-20) compared to an OR for anti–dsDNA – SLE of 1.26 (95% CI 1.12–1.41, p = 2.4E-04), with pheterogeneity<0.0005. SNPs in the SLE susceptibility loci BANK1, KIAA1542, and UBE2L3 showed evidence of association with anti–dsDNA + SLE and were not associated with anti–dsDNA – SLE. In conclusion, we identified differential genetic associations with SLE based on anti–dsDNA autoantibody production. Many previously identified SLE susceptibility loci may confer disease risk through their role in autoantibody production and be more accurately described as autoantibody propensity loci. Lack of strong SNP associations may suggest that other types of genetic variation or non-genetic factors such as environmental exposures have a greater impact on susceptibility to anti–dsDNA – SLE. [ABSTRACT FROM AUTHOR]

Objective: To reexamine the association between the neuronal sortilin-related receptor gene (SORL1) and Alzheimer disease (AD). Design: Comprehensive and unbiased meta-analysis of all published and unpublished data from case-control studies for the SORL1 single-nucleotide polymorphisms (SNPs) that had been repeatedly assessed across studies. Setting: Academic research institutions in the United States, the Netherlands, Canada, Belgium, the United Kingdom, Singapore, Japan, Sweden, Germany, France, and Italy. Participants: All published white and Asian casecontrol data sets, which included a total of 12 464 cases and 17 929 controls. Main Outcome Measures: Alzheimer disease according to the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) and the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (now known as the Alzheimer's Association). Results: In the white data sets, several markers were associated with AD after correction for multiple testing, including previously reported SNPs 8, 9, and 10 (P<.001). In addition, the C-G-C haplotype at SNPs 8 through 10 was associated with AD risk (P< .001). In the combined Asian data sets, SNPs 19 and 23 through 25 were associated with A Drisk (P<.001). The disease-associated alleles at SNPs 8, 9, and 10 (120 873 131-120 886 175 base pairs [bp]; C-G-C alleles), at SNP 19 (120 953 300 bp; G allele), and at SNPs 24 through 25 (120 988 611 bp; T and C alleles) were the same previously reported alleles. The SNPs 4 through 5, 8 through 10, 12, and 19 through 25 belong to distinct linkage disequilibrium blocks. The same alleles at SNPs 8 through 10 (C-G-C), 19 (G), and 24 and 25 (T and C) have also been associated with AD endophenotypes, including white matter hyperintensities and hippocampal atrophy on magnetic resonance imaging, cerebrospinal fluid measures of amyloid β-peptide 42, and full-length SORL1 expression in the human brain. Conclusion: This comprehensive meta-analysis provides confirmatory evidence that multiple SORL1 variants in distinct linkage disequilibrium blocks are associated with AD. [ABSTRACT FROM AUTHOR]

Primary objective: The purpose of the current study is to assess the role of the APOE genotype in post-traumatic seizure (PTS) development. Research design: A retrospective study of 322 adult Caucasians with a severe TBI and APOE genotype. Methods and procedures: Medical records were searched for PTS. Time to first seizure was categorized as early, late or delayed-onset PTS. Potential PTS associations by genotype, grouped genotype and allele were investigated. Main outcome and results: No statistically significant associations were found. However, two out of the four individuals (50%) with the E4/E4 genotype had late/delayed-onset PTS. Furthermore, none with a E2/E2 or E2/E4 genotype seized in the late periods. Conclusions: The results of this study may suggest 4/4 as a risk genotype for late/delayed onset PTS and a potential neuroprotective role of the E2 allele. However, this study did not definitively support a role for the APOE genotype in PTS susceptibility and indicates that larger populations are needed to fully evaluate the potential impact of APOE on PTS. [ABSTRACT FROM AUTHOR]

Apolipoprotein H (apoH, protein; APOH, gene) is a required cofactor for the production of antiphospholipid antibodies (APA). In this study we have examined whether genetic variation in the APOH gene affects variation in risk for systemic lupus erythematosus (SLE), occurrence of antiphospholipid antibodies (APA), anti-apoH, and plasma apoH concentrations. A total of 222 white SLE women were screened for four APOH polymorphisms (codons 88, 247, 306, and 316) by polymerase chain reaction, and for plasma apoH concentrations by ELISA. Of these, 29.3% were positive for APA (APA-positive group) and 31.1% for anti-apoH. None of the four APOH polymorphisms were significantly associated with variation in risk for SLE. The codons 306 and 316 polymorphisms showed significant, gene-dosage effects on plasma apoH concentrations (P<0.0001) and explained 30% and 13%, respectively, of the residual variation in apoH concentrations. No significant association was observed between anti-apoH status and APOH polymorphisms or plasma apoH levels. However, plasma apoH concentrations were significantly higher in patients positive for APA than in patients negative for APA (18.5±4.0 mg/dl vs 17.1±3.8 mg/dl; P=0.02). The distribution of the Trp316Ser polymorphism was significantly different between the APA-positive and APA-negative groups. The frequency of the mutant allele (Ser316) was significantly lower in the APA-positive group than the APA-negative group (3.1% vs 12.1% P<0.04), indicating that the Ser316 mutation is protective against the production of phospholipid-apoH dependent APA. Our data indicate that common genetic variation in the APOH gene is a significant determinant of plasma apoH variation in SLE patients, and the Trp316Ser polymorphism appears to provide protection against the production of APA in SLE patients. [ABSTRACT FROM AUTHOR]

Background: The relationship between subtle cognitive decline and Alzheimer's disease (AD) pathology as measured by biomarkers in settings outside of specialty memory clinics is not well characterized., Objective: To investigate how subtle longitudinal cognitive decline relates to neuroimaging biomarkers in individuals drawn from a population-based study in an economically depressed, small-town area in southwestern Pennsylvania, USA., Methods: A subset of participants without dementia (N = 115, age 76.53 years ± 6.25) from the Monongahela Youghiogheny Healthy Aging Team (MYHAT) study completed neuroimaging including magnetic resonance imaging (MRI) measures of AD-signature region cortical thickness and white matter hyperintensities (WMH), Pittsburgh compound B (PiB)-positron emission tomography (PET) for amyloid-β (Aβ) deposition, and [ 18 F]AV-1451-PET for tau deposition. Neuropsychological evaluations were completed at multiple timepoints up to 11 years prior to neuroimaging. Aβ positivity was determined using a regional approach. We used linear mixed models to examine neuroimaging biomarker associations with retrospective cognitive slopes in five domains and a global cognitive composite., Results: Among Aβ(+) participants (38%), there were associations between (i) tau Braak III/IV and language decline (p < 0.05), (ii) cortical thickness and both memory decline (p < 0.001) and global cognitive decline (p < 0.01), and (iii) WMH and decline in executive function (p < 0.05) and global cognition (p < 0.05). Among Aβ(-) participants, there was an association between tau Braak III/IV and decline on tests of attention/psychomotor speed (p < 0.05)., Conclusions: These findings confirm an Aβ-dependent early AD biomarker pathway, and suggest a possible Aβ-independent, non-AD process underlying subtle cognitive decline in a population-based sample of older adults without dementia., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: MG receives an annual honorarium for service as Associate Editor of the Journal of the American Geriatrics Society.

Here we present a plasma proteomics dataset that was generated to understand the importance of self-reported race for biomarker discovery in Alzheimer's disease. This dataset is related to the article "Why inclusion matters for Alzheimer's disease biomarker discovery in plasma" [1]. Plasma samples were obtained from clinically diagnosed Alzheimer's disease and cognitively normal adults of African American/Black and non-Hispanic White racial and ethnic backgrounds. Plasma was immunodepleted, digested, and isobarically tagged with commercial reagents. Tagged peptides were fractionated using high pH fractionation and resulting fractions analysed by liquid chromatography - mass spectrometry (LC-MS/MS & MS 3 ) analysis on an Orbitrap Fusion Lumos mass spectrometer. The resulting data was processed using Proteome Discoverer to produce a list of identified proteins with corresponding tandem mass tag (TMT) intensity information., Competing Interests: The authors have declared no conflicts of interest., (© 2021 The Authors.)

Database Urls: http://www.regulomedb.org/;https://www.broadinstitute.org/mpg/snap/., (© The Author(s) 2017. Published by Oxford University Press.)

Objective: There is a recognized but poorly understood relationship between late-life depression (LLD) and progressive dementia. Both cognitive impairment co-occurring with LLD and a late age-of-onset of first lifetime depressive episode appear to be associated with subsequent progressive dementia. A history of major depression, especially when the first onset occurs in late-life, has been identified as a risk factor for Alzheimer's disease (AD). The major genetic risk factor for sporadic AD is carrying one or more apolipoprotein E4 (APOE4) alleles. We hypothesized that the association between LLD and dementia risk would be mediated by APOE4, specifically that APOE4 allele frequency would be associated with cognitive impairment and later age-of-depression-onset. We also predicted that APOE4 allele frequency would be increased among subjects with LLD., Methods: We compared the distribution of APOE2, APOE3, and APOE4 alleles in groups of LLD (n=160), AD (n=568) and elderly control (EC; n=156) subjects., Results: The allele distribution of the cognitively impaired LLD subgroup was not different from either the cognitively normal subgroup or the EC group but was different from the AD group. However, mean age-of-onset of depression in APOE4 carriers (51.4+/-20.7) was significantly lower than non-carriers (58.8+/-16.8). The allele distribution in LLD overall was significantly different from the AD but not the EC group., Conclusions: The finding that neither LLD, accompanying cognitive impairment, nor late age-of-onset was associated with an increased APOE4 allele frequency suggests that LLD acts as a risk factor for developing AD as well as non-AD dementia through mechanisms independent of APOE4. The unexpected finding that age-of-onset of LLD was significantly reduced in APOE4 carriers is similar to the association between APOE4 and age-of-onset in AD. Replication of the association of APOE4 with earlier age-of-depression-onset is indicated., (Copyright 2003 John Wiley & Sons, Ltd.)

Objective: Apolipoprotein E isoform (E4) has been posited to affect outcomes after central nervous system injury. This project sought to determine the relationship between the apoE4 allele and the recovery of amino acid neurotransmitters (aspartate, glutamate, and lactate/pyruvate ratio [L/P]) following a traumatic brain injury (TBI) after controlling for patient characteristics., Design: This prospective clinical study examined neurotransmitters and L/P within the cerebrospinal fluid and compared the trends by apoE genotypes., Setting: Adults with TBI were recruited from a neurotrauma intensive care unit within a trauma I university medical center., Patients: Ninety-one patients were enrolled into the study after a severe TBI (Glasgow Coma Scale [GCS] score,