Allele Status Research Articles

Health-Related Behaviors and Risk of Common Age-Related Brain Diseases Across Severities of Genetic Risk.

The 21-point Brain Care Score (BCS) is an index that ranks behaviors and clinical measurements with the aim of encouraging lifestyle adjustments to lower the incidence of age-related brain disease, including stroke, late-life depression (LLD), and dementia. A higher BCS at baseline is associated with a lower risk of these outcomes. We aimed to investigate whether the associations between BCS and stroke, LLD, and dementia risks are independent of genetic predisposition for these conditions and quantify the effect of healthy lifestyle across genetic risk distributions for these outcomes. Using the UK Biobank (UKB) prospective cohort study, we computed baseline BCSs and polygenic scores to estimate genetic predisposition for stroke and LLD and APOE ε allele status to stratify dementia risk. As for outcomes again in UKB, we measured incidence of stroke, LLD, and dementia. We used multivariate Cox proportional hazard models to assess associations between BCS, genetic predisposition, and these outcomes. We also conducted stratified and interaction analyses to estimate the incidence of these outcomes across quartiles of genetic risk and BCS. We included 368,340 UKB participants (median age 58 years (interquartile range 51-63 years), 46.3% male). Independent of genetic risk, a 5-point increase in BCS corresponded to lowered hazards of stroke (hazard ratio [HR] 0.70, 95% CI 0.68-0.73), LLD (HR 0.65, 95% CI 0.63-0.67), and dementia (HR 0.82, 95% CI 0.78-0.85). Incidences of all 3 outcomes were higher among participants with high genetic risk of these outcomes. However, these increased risks were offset for individuals with a higher BCS (incidence rates per 1,000 person-years were 2.76 vs 1.19 for stroke, 7.34 vs 4.46 for LLD, and 3.64 vs 2.05 for dementia, when comparing low and high BCS). Across different genetic predispositions for stroke, LLD, and dementia, healthier lifestyle behaviors are protective for brain health, demonstrating the nondeterminism of genetic risk. Furthermore, differences in BCS behave as aggregate risk estimators of all 3 outcomes. Further work is needed to prospectively investigate the utility and performance of the BCS as a targeted intervention in populations at elevated genetic risk of age-related brain disease.

Are TP53 mutations all alike?

TP53 is mutated in 10 to 15% of cases of acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) and is associated with a previous exposure to cytotoxic therapy, complex cytogenetic abnormalities, and a poor prognosis. Recent data have established the importance of TP53-mutant allele status, the determination of which requires specific genetic testing. Compared with monoallelic disease, multihit TP53-mutant AML/MDS is associated with chromosomal abnormalities and decreased overall survival. Most TP53 mutations are missense mutations that localize to the DNA binding domain. Hot-spot mutations involving residues R175, Y220, G245, R248, R273, or R282 represent approximately 35% of all TP53 missense mutations in AML/MDS. There is evidence that these hot-spot mutations may have dominant negative or gain-of-function properties. Here we review this evidence and discuss its potential impact on patient outcomes and clinical management.

Biomarker and neuropsychological correlates of the N400 event-related potential in Alzheimer's disease

ObjectiveThe current study sought to characterize the relationship of the N400 (N4) effect event-related potential to Alzheimer's disease (AD) biomarkers and broader cognition in older adults on the late-life cognitive continuum. MethodParticipants who were cognitively intact (n = 43), or had amnestic mild cognitive impairment (MCI; n = 19), or mild AD (n = 12), completed a word-pair judgement task during concurrent EEG recording to elicit the N400. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and biomarker data (PET-imaged beta-amyloid (aβ) deposition, apolipoprotein-E ε4 (APOE4) allele status, hippocampal volumes) were collected as part of a larger study. ResultsThe AD group had slower response times and poorer accuracy on the word-pair judgement task than the intact group. The N4 effect was smaller and occurred later in AD relative to intact participants. MCI participants' values were intermediate. N4 effect amplitudes were not associated with RBANS scores but were positively associated with aβ deposition. Conversely, poorer performance across most RBANS Indexes and the Total score was associated with longer N4 latencies. There was also a negative association between hippocampal volumes and the N4 latency and a positive association between aβ deposition and latency. Finally, the latency of the N4 independently predicted variance in RBANS Total scores, above and beyond aβ deposition, hippocampal volumes, and APOE4 allele status. ConclusionsThese findings support the relevance of the N4 effect in individuals along the late-life cognitive continuum, and motivate future studies into its potential as a longitudinal predictor in AD.

Pure LATE-NC: Frequency, clinical impact, and the importance of considering APOE genotype when assessing this and other subtypes of non-Alzheimer’s pathologies

Pure limbic-predominant age-related TDP-43 encephalopathy neuropathologic changes (pure LATE-NC) is a term used to describe brains with LATE-NC but lacking intermediate or severe levels of Alzheimer’s disease neuropathologic changes (ADNC). Focusing on pure LATE-NC, we analyzed data from the National Alzheimer’s Coordinating Center (NACC) Neuropathology Data Set, comprising clinical and pathological information aggregated from 32 NIH-funded Alzheimer’s Disease Research Centers (ADRCs). After excluding subjects dying with unusual conditions, n = 1,926 autopsied subjects were included in the analyses. For > 90% of these participants, apolipoprotein E (APOE) allele status was known; 46.5% had at least one APOE 4 allele. In most human populations, only 15–25% of people are APOE ε4 carriers. ADRCs with higher documented AD risk allele (APOE or BIN1) rates had fewer participants lacking ADNC, and correspondingly low rates of pure LATE-NC. Among APOE ε4 non-carries, 5.3% had pure LATE-NC, 37.0% had pure ADNC, and 3.6% had pure neocortical Lewy body pathology. In terms of clinical impact, participants with pure LATE-NC tended to die after having received a diagnosis of dementia: 56% died with dementia among APOE ε4 non-carrier participants, comparable to 61% with pure ADNC. LATE-NC was associated with increased Clinical Dementia Rating Sum of Boxes (CDR-SOB) scores, i.e. worsened global cognitive impairments, in participants with no/low ADNC and no neocortical Lewy body pathology (p = 0.0023). Among pure LATE-NC cases, there was a trend for higher LATE-NC stages to be associated with worse CDR-SOB scores (p = 0.026 for linear trend of LATE-NC stages). Pure LATE-NC was not associated with clinical features of disinhibition or primary progressive aphasia. In summary, LATE-NC with no or low levels of ADNC was less frequent than pure ADNC but was not rare, particularly among individuals who lacked the APOE 4 allele, and in study cohorts with APOE 4 frequencies similar to those in most human populations.

An abdominal obesity missense variant in the adipocyte thermogenesis gene TBX15 is implicated in adaptation to cold in Finns.

Mechanisms of abdominal obesity GWAS variants have remained largely unknown. To elucidate these mechanisms, we leveraged subcutaneous adipose tissue (SAT) single nucleus RNA-sequencing and genomics data. After discovering that heritability of abdominal obesity is enriched in adipocytes, we focused on a SAT unique adipocyte marker gene, the transcription factor TBX15, and its abdominal obesity-associated deleterious missense variant, rs10494217. The allele frequency of rs10494217 revealed a north-to-south decreasing gradient, with consistent significant FST values observed for 25 different populations when compared to Finns, a population with a history of genetic isolation. Given the role of Tbx15 in mouse thermogenesis, the frequency may have increased as an adaptation to cold in Finns. Our selection analysis provided significant evidence of selection for the abdominal obesity risk allele T of rs10494217 in Finns, with a north-to-south decreasing trend in other populations, and demonstrated that latitude significantly predicts the allele frequency. We also discovered that the risk allele status significantly affects SAT adipocyte expression of multiple adipocyte marker genes in trans in two cohorts. Two of these trans genes have been connected to thermogenesis, supporting the thermogenic effect of the TBX15 missense variant as a possible cause of its selection. Adipose expression of one trans gene, a lncRNA, AC002066.1, was strongly associated withadipocyte size, implicating it in metabolically unhealthy adipocyte hypertrophy. In summary, the abdominal obesity variant rs10494217 was selected in Finns, and individuals with the risk allele have trans effects on adipocyte expression of genes relating to thermogenesis and adipocyte hypertrophy.

Overall survival in TP53-mutated AML and MDS.

TP53 mutations in patients with AML and MDS frequently portend a poor prognosis, related to both p53 allele status and blast count. In 2022, the ICC and WHO released updated guidelines for classifying p53-mutated AML/MDS. The characteristics of p53 mutations, their associated co-mutations, and their effects on overall survival (OS) are not known in the context of these new guidelines. A retrospective chart review was undertaken for all patients with AML or MDS and at least one TP53 mutation detected on next generation sequencing (NGS) at Yale New Haven Hospital from 2015 to 2023. All patients (N = 210) met criteria for one of the 5 diagnostic classes based on WHO and ICC guidelines. Kaplan-Meier curves with associated log-rank testing and Cox proportional hazards model quantified the effects of clinical and molecular data on survival. Multi-hit pathogenic mutations were related to poorer OS in MDS but not AML using either the WHO (p = .02) or the ICC (p = .01) diagnostic criteria. The most significant predictors of OS in the sample overall were platelet count < 50K (HR: 2.01, 95% CI [1.47, 2.75], p < .001) and TP53 VAF ≤ 40% (HR: 0.68, 95% CI[0.50, 0.91], p = .01). Blast count ranges, complex karyotype, and p53 mutation type or location, showed no association with OS. In our cohort defined by the 2022 ICC and WHO criteria, VAF and thrombocytopenia, rather than blast count or p53 mutation features, significantly predicted OS. These results speak to each criteria's ability to identify cases of similarly aggressive disease biology and prognosis.

Genomic and Serological Rheumatoid Arthritis Biomarkers, MUC5B Promoter Variant, and Interstitial Lung Abnormalities.

Rheumatoid arthritis (RA) has been implicated in interstitial lung disease (ILD) as majority of studies have been comprised of patients with known RA. However, it remains unclear whether an underlying risk for RA in combination with genetic risk for pulmonary fibrosis is associated with radiological markers of early lung injury and fibrosis in broader population samples. Determine whether genetic and serological biomarkers of RA risk in combination with the MUC5B (rs35705950) risk allele (T) are associated with interstitial lung abnormalities (ILA) on computed tomography (CT) scans. Associations of RA-risk HLA-DRB1 alleles (*04:01, *04:08, *04:05, *04:04, *10:01) and serum RA autoantibodies with ILA in the Multi-Ethnic Study of Atherosclerosis (MESA, n=4,018) and COPDGene (n=5,963) cohorts were modeled using logistic regression and adjusted for age, sex, self-reported race and ethnicity, smoking history, body mass index, and principal components of genetic ancestry. The prevalence of an RA risk HLA-DRB1 allele was 16.5% and 21.9% in MESA and COPDGene, respectively. ILA was present in 3.9% and 11% in MESA and COPDGene, respectively. An RA risk HLA-DRB1 allele was not significantly associated with ILA in MESA and COPDGene. In MESA, higher serum levels of IgA rheumatoid factor (RF) and anti-cyclic citrullinated peptide were associated with an odds ratio (OR) for ILA of 1.20 (95% CI 1.07-1.35) and 1.19 (95% CI 1.04-1.37), respectively. Among smokers without baseline ILA, per doubling of IgM RF was associated with an OR for ILA 10 years later of 1.25 (95% CI 1.08-1.43). Associations were not significantly different by MUC5B risk allele status. RA-related HLA-DRB1 alleles were not associated with ILA, whereas higher serum levels of IgM RF among smokers without baseline ILA were associated with subsequent ILA.

Redesigning soybean with improved oil and meal traits.

Soybean seed oil and meal composition traits can be combined without interference to provide additional value to the crop. Soybean [Glycine max (L.) Merr.] is an important crop worldwide; its overall value comes from seed oil and high protein meal. The development of soybean varieties with allele combinations for improved oil and meal quality is expected to provide a compositional value bundle for soybean. The high oleic and low linolenic acid seed oil trait (HOLL; > 70% oleic and < 3% linolenic acid) is targeted to optimize the health and functional properties of soybean oil. For soybean meal, metabolizable energy is improved by altering the carbohydrate profile with increased sucrose and decreased anti-nutritional factors, raffinose family of oligosaccharides (RFOs). Previous research identified four variant alleles of fatty acid desaturase (FAD) genes and two raffinose synthase (RS) genes necessary for the HOLL trait in soybean oil and Low or Ultra-Low (UL) RFO traits in soybean meal, respectively. We employed a molecular marker-assisted breeding approach to combine six alleles conferring the desired soybean oil and meal value traits. Eight environment field trials were conducted with twenty-four soybean lines to evaluate phenotypic interactions among the variant alleles of FAD and RS genes. The results indicated that the four FAD gene alleles conditioned the HOLL fatty acid profile of the seed oil regardless of the allele status of the RS genes. Independent of the allele combination of the FAD genes, soybean with two variant alleles of the RS genes had the desired RFO trait in the seeds. The results confirm the feasibility of soybean variety development with this unique combination of oil and meal traits.

A prediction model of dementia conversion for mild cognitive impairment by combining plasma pTau181 and structural imaging features.

The early stages of Alzheimer's disease (AD) are no longer insurmountable. Therefore, identifying at-risk individuals is of great importance for precise treatment. We developed a model to predict cognitive deterioration in patients with mild cognitive impairment (MCI). Based on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, we constructed models in a derivation cohort of 761 participants with MCI (138 of whom developed dementia at the 36th month) and verified them in a validation cohort of 353 cognitively normal controls (54 developed MCI and 19 developed dementia at the 36th month). In addition, 1303 participants with available AD cerebrospinal fluid core biomarkers were selected to clarify the ability of the model to predict AD core features. We assessed 32 parameters as candidate predictors, including clinical information, blood biomarkers, and structural imaging features, and used multivariable logistic regression analysis to develop our prediction model. Six independent variables of MCI deterioration were identified: apolipoprotein E ε4 allele status, lower Mini-Mental State Examination scores, higher levels of plasma pTau181, smaller volumes of the left hippocampus and right amygdala, and a thinner right inferior temporal cortex. We established an easy-to-use risk heat map and risk score based on these risk factors. The area under the curve (AUC) for both internal and external validations was close to 0.850. Furthermore, the AUC was above 0.800 in identifying participants with high brain amyloid-β loads. Calibration plots demonstrated good agreement between the predicted probability and actual observations in the internal and external validations. We developed and validated an accurate prediction model for dementia conversion in patients with MCI. Simultaneously, the model predicts AD-specific pathological changes. We hope that this model will contribute to more precise clinical treatment and better healthcare resource allocation.

Fish consumption, cognitive impairment and dementia: an updated dose-response meta-analysis of observational studies

BackgroundCognitive impairment is projected to affect a preponderant proportion of the aging population. Lifelong dietary habits have been hypothesized to play a role in preventing cognitive decline. Among the most studied dietary components, fish consumptionhas been extensively studied for its potential effects on the human brain.AimsTo perform a meta-analysis of observational studies exploring the association between fish intake and cognitive impairment/decline and all types of dementia.MethodsA systematic search of electronic databases was performed to identify observational studies providing quantitative data on fish consumption and outcomes of interest. Random effects models for meta-analyses using only extreme exposure categories, subgroup analyses, and dose-response analyses were performed to estimate cumulative risk ratios (RRs) and 95% confidence intervals (CIs).ResultsThe meta-analysis comprised 35 studies. Individuals reporting the highest vs. the lowest fish consumption were associated with a lower likelihood of cognitive impairment/decline (RR = 0.82, 95% CI: 0.75, 0.90, I2 = 61.1%), dementia (RR = 0.82, 95% CI: 0.73, 0.93, I2 = 38.7%), and Alzheimer’s disease (RR = 0.80, 95% CI: 0.67, 0.96, I2 = 20.3%). The dose-response relation revealed a significantly decreased risk of cognitive impairment/decline and all cognitive outcomes across higher levels of fish intake up to 30% for 150 g/d (RR = 0.70, 95% CI: 0.52, 0.95). The results of this relation based on APOE ε4 allele status was mixed based on the outcome investigated.ConclusionsCurrent findings suggest fish consumption is associated with a lower risk of cognitive impairment/decline in a dose-response manner, while for dementia and Alzheimer’s disease there is a need for further studies to improve the strength of evidence.

Efficacy and Safety of Exogenous Ketones in People with Mild Neurocognitive Disorder and Alzheimer's Disease: A Systematic Literature Review.

Mild neurocognitive disorder (NCD), formally known as mild cognitive impairment, is usually the clinical stage preceding the development of Alzheimer's disease (AD), the most prevalent major NCD, and other causes of dementia. Glucose is a major source of energy for human brain metabolism and the uptake of glucose is reduced in patients with mild NCD, AD, and other NCDs. Unlike glucose, the uptake of ketones remains normal in people with mild NCD and AD, suggesting that the use of ketone bodies may compensate for glucose energy deficiency in patients with mild NCD and AD. The aim of this systematic review was to summarize the efficacy and safety of exogenic ketones, including medium chain triglycerides (MCTs), on cognitive function in patients with mild NCD and AD. The Embase, MEDLINE, MEDLINE In-Process, PubMed Ahead-of-Print, Cochrane Central Register of Controlled Trials, Europe PMC databases were searched from inception to April 2022. Studies reporting cognitive function efficacy and safety outcomes from randomized controlled trials of exogenic ketones in patients with mild NCD and AD were included. Data were extracted by 1 reviewer and checked by a second reviewer. Risk of bias was assessed using the Cochrane risk of bias tool, version 2. This review identified 13 individual trials investigating the efficacy and safety of MCT or coconut oil for patients with mild NCD or with AD. Because of the heterogeneity of the studies, a narrative synthesis was used. Overall, improvements associated with exogenic ketones were observed in multiple aspects of cognitive abilities, although the large heterogeneity between the included studies makes it difficult to draw firm conclusions from the current literature. Although some studies investigated the impact of the apolipoprotein E ε4 allele status on treatment efficacy, the current data are insufficient to conclude whether such an effect is present. PROSPERO registration No. CRD42022336664.

Differences in the Distribution of Aβ in the Brain between U.S. Veterans and Adults aged 62+ and suffering from Alzheimer's Disease.

Elevated concentration of amyloids in the cerebrum results in elevated risks for cerebral hemorrhage and early AD onset following early depression/dementia onset. In this study, we compare patterns of amyloid depositions across eight regions of interest of the human brain between U.S. Veterans and non-Veterans adults aged 62+. Data were taken from the ADNI and DoD-ADNI studies. A pseudo-randomization algorithm was applied to achieve comparability, reduce bias due to age mismatching, and account for non-treatment-related differences between subsamples extracted from DoD-ADNI and ADNI databases. The pool of participants included data about age, race, apolipoprotein ε4 allele (APOE) status, modified Hachinski Ischemic Score, education level, and geriatric depression score, which were used to build a propensity score. Aβ concentration, resulting from the PET image analysis, in key brain regions of interest, and two categorical variables describing the 0.79 and 1.11 cutoffs were used as outcomes, while the Veteran and AD status were used as predictors. To balance subsamples, we applied a pseudo-randomization algorithm, eliminating the observed sources of heterogeneity. We used a generalized linear model for continuous variables and the logistic regression model for binary variables. The pattern of the Aβ distribution in Veteran's brains was found to be different from the classic AD pattern. The amyloid depositions following Veteran status were concentrated in cerebellar gray matter and the cerebellum in general. In contrast, the AD pattern shows more Aβ depositions in the frontal lobe, cingulate cortex, parietal, and temporal lobes, along with higher whole-cerebrum concentration of amyloids. Since Florbetapir PET cannot distinguish between senile plaques and depositions in blood vessels, the elevated concentration of amyloids in a cerebellum for participants with the Veteran status may suppose elevated risks for cerebral hemorrhage and early AD onset following early depression/dementia onset.

Sickle cell trait, APOL1 risk allele status and chronic kidney disease among ART-experienced adults living with HIV in northern Nigeria.

We sought to determine the prevalence of sickle cell trait (SCT) and apolipoprotein-1 (APOL1) risk variants in people living with HIV (PLWH) in Nigeria, and to establish if SCT and APOL1 high-risk status correlate with estimated glomerular filtration rate (eGFR) and/or prevalent chronic kidney disease (CKD). Baseline demographic and clinical data were obtained during three cross-sectional visits. CKD was defined as having an eGFR<60mL/min/1.73m2. We collected urine specimens to determine urine albumin-creatine ratio and blood samples for sickle cell genotyping, APOL1 testing, and for creatinine/cystatin C assessment. The associations between SCT, APOL1 genotype, and eGFR/CKD stages/CKD were investigated using linear/ordinal logistic/logistic regression models, respectively. Of 2443 participants, 599 (24.5%) had SCT, and 2291 (93.8%) had a low-risk APOL1 genotype (0 or 1 risk variant), while 152 (6.2%) had high-risk genotype (2 allele copies). In total, 108 participants (4.4%) were diagnosed with CKD. In adjusted analyses, SCT was associated with lower eGFR (adjusted mean difference [aMD]= -2.33, 95% CI -4.25, -0.42), but not with worse CKD stages, or increased odds of developing CKD. Participants with the APOL1 high risk genotype were more likely to have lower eGFR (aMD= -5.45, 95% CI -8.87, -2.03), to develop CKD (adjusted odds ratio [aOR] = 1.97, 95% CI: 1.03, 3.75), and to be in worse CKD stages (aOR = 1.60, 95% CI: 1.12, 2.29) than those with the low-risk genotype. There was no evidence of interaction between SCT and APOL1 genotype on eGFR or risk of CKD. Our findings highlight the multifaceted interplay of genetic factors in the pathogenesis of CKD in PLWH.

Therapy-related myeloid neoplasms with single-hit TP53 mutations share the clinical, molecular, and survival characteristics of their multi-hit counterparts

Recent updates in the classification of myeloid neoplasms (MNs) recognize the poor prognostic impact of TP53 mutations, with particular emphasis on the TP53 allele status. Studies on the effect of TP53 allele status exclusively in therapy-related MNs (t-MNs) are lacking. We compared the clinicopathologic and survival characteristics of t-MNs with single-hit (SH) and multi-hit (MH) TP53 mutations. A total of 71 TP53-mutated t-MNs were included, including 56 (78.9%) MH and 15 (21.1%) SH. Both groups showed comparable genetic profiles with an excess of high-risk karyotypes and a paucity of other co-mutated genes. TP53 was the sole detectable mutation in 73.3% of SH and 75.0% of MH cases. The overall survival (OS) of SH TP53-mutated t-MNs was not significantly different from MH cases (median survival: 233 vs.273 days, p = 0.70). Our findings suggest that t-MNs with SH TP53 mutations share the poor prognostic and biologic profile of their MH counterparts.

Impact of work type and APOE-e4 status on cognitive functioning in older women

Prior research indicates that APOE-e4 allele(s) and working without compensation may be independently associated with risk for cognitive decline. This study investigated whether the interaction of type of work (paid versus unpaid) and presence of APOE-e4 allele(s) was associated with cognitive dysfunction in women in mid- and late-life. Participants included 340 females (mean age = 74.7 years) from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) dataset. A two-way ANOVA to assess the simple main effects of type of work and APOE-e4 allele status on cognition as well as their interaction was performed. A two-way ANCOVA including age, education, and marital status as covariates was also conducted. The presence of one or two APOE-e4 allele(s) and unpaid work was associated with greater cognitive dysfunction. A significant interaction effect revealed engagement in paid work, regardless of the presence of APOE-e4 allele(s), was associated with better cognitive functioning. Consistent with prior literature, women who engage in unpaid forms of labor for the majority of their life may be at higher risk for cognitive decline, regardless of presence of APOE-e4 allele(s). Further research is needed to identify the factors related to unpaid labor that may increase risk for cognitive dysfunction.

LDLR gene variant rs688 TT genotype; genetic association with obesity in Familial Hypercholesterolemia patients

The predominant genetic risk factor for familial hypercholesterolemia along with obesity is LDLR allele status. These receptors maintain cellular cholesterol homeostasis. For instance, a common SNP rs688 in different populations has been reported to be associated with elevatedplasma LDL, resulting in hypercholesterolemia. The potential role of variant rs688 with obesity in FH patients was observed. This is a case-control study with 120 blood samples of clinically diagnosed obese familial hypercholesterolemia patients by physicians and 120 healthy individuals’ blood samples were recruited for the study. Genomic DNA was extracted from blood samples. By using Tetra ARMS PCR, genotyping of LDLR rs688 (C&gt;T) exon 12 gene variation was performed. Moreover, BMI, BP, and BSL of obese FH patients were alsoobtained; a chi-square test was performed on the obtained data to evaluate the association between rs688 and obese FH patients. Genotype CC, CT, and TT frequencies reported in the obese FH patients’ group were 0.33, 0.41, and 0.25, while in healthy individuals were 0.37, 0.41, and 0.21 respectively. Chi–square values showed a significant association with BMI, BP, and BSL. It was assessed that there is a 4% increased susceptibility of FH development along with obesity in individuals with TT genotype. So, for obese familial hypercholesterolemia, the LDLR rs688 C&gt;T gene variation can be used as a predisposing genetic marker.

Suboptimal self-reported sleep efficiency and duration are associated with faster accumulation of brain amyloid beta in cognitively unimpaired older adults.

This study investigated whether self-reported sleep quality is associated with brain amyloid beta (Aβ) accumulation. Linear mixed effect model analyses were conducted for 189 cognitively unimpaired (CU) older adults (mean±standard deviation 74.0±6.2; 53.2% female), with baseline self-reported sleep data, and positron emission tomography-determined brain Aβ measured over a minimum of three time points (range 33.3-72.7 months). Analyses included random slopes and intercepts, interaction for apolipoprotein E (APOE) ε4 allele status, and time, adjusting for sex and baseline age. Sleep duration<6hours, in APOE ε4 carriers, and sleep efficiency<65%, in the whole sample and APOE ε4 non-carriers, is associated with faster accumulation of brain Aβ. These findings suggest a role for self-reported suboptimal sleep efficiency and duration in the accumulation of Alzheimer's disease (AD) neuropathology in CU individuals. Additionally, poor sleep efficiency represents a potential route via which individuals at lower genetic risk may progress to preclinical AD. In cognitively unimpaired older adults self-report sleep is associated with brain amyloid beta (Aβ) accumulation.Across sleep characteristics, this relationship differs by apolipoprotein E (APOE) genotype.Sleep duration<6hours is associated with faster brain Aβ accumulation in APOE ε4 carriers.Sleep efficiency< 65% is associated with faster brain Aβ accumulation in APOE ε4 non-carriers.Personalized sleep interventions should be studied for potential to slow Aβ accumulation.

Dementia risk and thalamic nuclei volumetry in healthy midlife adults: the PREVENT Dementia study.

A reduction in the volume of the thalamus and its nuclei has been reported in Alzheimer's disease, mild cognitive impairment and asymptomatic individuals with risk factors for early-onset Alzheimer's disease. Some studies have reported thalamic atrophy to occur prior to hippocampal atrophy, suggesting thalamic pathology may be an early sign of cognitive decline. We aimed to investigate volumetric differences in thalamic nuclei in middle-aged, cognitively unimpaired people with respect to dementia family history and apolipoprotein ε4 allele carriership and the relationship with cognition. Seven hundred participants aged 40-59 years were recruited into the PREVENT Dementia study. Individuals were stratified according to dementia risk (approximately half with and without parental dementia history). The subnuclei of the thalamus of 645 participants were segmented on T1-weighted 3 T MRI scans using FreeSurfer 7.1.0. Thalamic nuclei were grouped into six regions: (i) anterior, (ii) lateral, (iii) ventral, (iv) intralaminar, (v) medial and (vi) posterior. Cognitive performance was evaluated using the computerized assessment of the information-processing battery. Robust linear regression was used to analyse differences in thalamic nuclei volumes and their association with cognitive performance, with age, sex, total intracranial volume and years of education as covariates and false discovery rate correction for multiple comparisons. We did not find significant volumetric differences in the thalamus or its subregions, which survived false discovery rate correction, with respect to first-degree family history of dementia or apolipoprotein ε4 allele status. Greater age was associated with smaller volumes of thalamic subregions, except for the medial thalamus, but only in those without a dementia family history. A larger volume of the mediodorsal medial nucleus (Pfalse discovery rate = 0.019) was associated with a faster processing speed in those without a dementia family history. Larger volumes of the thalamus (P = 0.016) and posterior thalamus (Pfalse discovery rate = 0.022) were associated with significantly worse performance in the immediate recall test in apolipoprotein ε4 allele carriers. We did not find significant volumetric differences in thalamic subregions in relation to dementia risk but did identify an interaction between dementia family history and age. Larger medial thalamic nuclei may exert a protective effect on cognitive performance in individuals without a dementia family history but have little effect on those with a dementia family history. Larger volumes of posterior thalamic nuclei were associated with worse recall in apolipoprotein ε4 carriers. Our results could represent initial dysregulation in the disease process; further study is needed with functional imaging and longitudinal analysis.

Atrophy of the cholinergic regions advances from early to late mild cognitive impairment.

We investigated the volumetric changes in the components of the cholinergic pathway for patients with early mild cognitive impairment (EMCI) and those with late mild cognitive impairment (LMCI). The effect of patients' apolipoprotein 4 (APOE-ε4) allele status on the structural changes were analyzed. Structural magnetic resonance imaging data were collected. Patients' demographic information, plasma data, and validated global cognitive composite scores were included. Relevant features were extracted for constructing machine learning models to differentiate between EMCI (n = 312) and LMCI (n = 541) and predict patients' neurocognitive function. The data were analyzed primarily through one-way analysis of variance and two-way analysis of covariance. Considerable differences were observed in cholinergic structural changes between patients with EMCI and LMCI. Cholinergic atrophy was more prominent in the LMCI cohort than in the EMCI cohort (P < 0.05 family-wise error corrected). APOE-ε4 differentially affected cholinergic atrophy in the LMCI and EMCI cohorts. For LMCI cohort, APOE-ε4 carriers exhibited increased brain atrophy (left amygdala: P = 0.001; right amygdala: P = 0.006, and right Ch123, P = 0.032). EMCI and LCMI patients showed distinctive associations of gray matter volumes in cholinergic regions with executive (R2 = 0.063 and 0.030 for EMCI and LMCI, respectively) and language (R2 = 0.095 and 0.042 for EMCI and LMCI, respectively) function. Our data confirmed significant cholinergic atrophy differences between early and late stages of mild cognitive impairment. The impact of the APOE-ε4 allele on cholinergic atrophy varied between the LMCI and EMCI groups.

APOE ε4 allele status modulates the spatial patterns of progressive atrophy in the temporal lobes after mild traumatic brain injury.

We evaluated how the apolipoprotein E (APOE) ε4 allele modulated the spatial patterns of longitudinal atrophy in the Alzheimer's disease-vulnerable brain areas of patients with mild traumatic brain injury (mTBI) from the acute to chronic phase post injury. Fifty-nine adult patients with acute mTBI and 48 healthy controls with APOE ε4 allele testing underwent T1-weighted magnetic resonance imaging and neuropsychological assessments with 6 to 12 months of follow-up. Progressive brain volume loss was compared voxel-wise in the temporal lobes. Patients with the APOE ε4 allele presented significant longitudinal atrophy in the left superior and middle temporal gyri, where the progressive gray matter volume loss predicted longitudinal impairment in language fluency, whereas mTBI APOE ε4 allele noncarriers showed mainly significant longitudinal atrophy in the medial temporal lobes, without significant neuropsychological relevance. The atrophy progression observed in mTBI patients with the APOE ε4 allele may increase the possibility of developing a specific phenotype of Alzheimer's disease with language dysfunction. The apolipoprotein E (APOE) ε4 allele and mild traumatic brain injury (mTBI) are risk factors for Alzheimer's disease (AD) progression.It is unclear how the interaction of mTBI with the APOE ε4 allele impacts the progressive atrophy topography in AD-vulnerable brain regions.In this study, patients with the APOE ε4 allele showed progressive atrophy patterns similar to the early stage of logopenic variant of primary progressive aphasia (lvPPA) phenotype of AD. APOE ε4 allele carriers with mTBI history may be at the risk of developing a given AD phenotype with language dysfunction.