Genetic Protective Factors Research Articles

Genetic Variants in the Adhesive G Protein-Coupled Receptor ADGRG6 are Associated with Increased Susceptibility to COPD in the Elderly Han Chinese Population of Southern China.

Mutations in ADGRG6 are associated with a variety of cancers and multiple types of diseases. However, the impact of genetic variations in ADGRG6 on chronic obstructive pulmonary disease (COPD) susceptibility has not yet been evaluated. Considering the high prevalence of COPD among the elderly population in China, this study specifically targets the elderly Han population in Southern China as the study subject. Following the acquisition of participants' whole-genome DNA, genotyping was conducted using the Agena MassARRAY platform. The online tool 'SNPStats', which utilizes logistic regression, was employed to analyze and assess the correlation. Multi-factor dimensionality reduction was utilized to clarify the impact of "SNP-SNP" interactions on COPD risk. The False-Positive Report Probability (FPRP) was applied to determine whether significant results are noteworthy findings. The mutant allele "C" of rs11155242 was a protective genetic factor against COPD susceptibility (OR = 0.57, 95% CI = 0.36 to 0.91, p = 0.017). The heterozygous mutant genotype "CA" of rs11155242 was found to be significantly associated with reduced COPD risk (CA Vs AA: OR = 0.53, 95% CI = 0.32 to 0.90, p = 0.018). ADGRG6-rs11155242 was found to be strongly associated with a reduced risk of COPD in males, non-smokers, and subjects with a BMI below 24 kg/m2 (OR < 1, p < 0.05). The FPRP analysis indicated that the positive results identified in this study are noteworthy new findings. The mutant allele "C" and mutant genotype "CA" of rs11155242 act as protective genetic factors against COPD susceptibility. This study will provide a new research direction for the personalized prevention and treatment of COPD in the elderly Han population in southern China, and lay a potential scientific basis.

Haploinsufficiency and Alzheimer's Disease: The Possible Pathogenic and Protective Genetic Factors.

Alzheimer's disease (AD) is a complex neurodegenerative disorder influenced by various genetic factors. In addition to the well-established amyloid precursor protein (APP), Presenilin-1 (PSEN1), Presenilin-2 (PSEN2), and apolipoprotein E (APOE), several other genes such as Sortilin-related receptor 1 (SORL1), Phospholipid-transporting ATPase ABCA7 (ABCA7), Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), Phosphatidylinositol-binding clathrin assembly protein (PICALM), and clusterin (CLU) were implicated. These genes contribute to neurodegeneration through both gain-of-function and loss-of-function mechanisms. While it was traditionally thought that heterozygosity in autosomal recessive mutations does not lead to disease, haploinsufficiency was linked to several conditions, including cancer, autism, and intellectual disabilities, indicating that a single functional gene copy may be insufficient for normal cellular functions. In AD, the haploinsufficiency of genes such as ABCA7 and SORL1 may play significant yet under-explored roles. Paradoxically, heterozygous knockouts of PSEN1 or PSEN2 can impair synaptic plasticity and alter the expression of genes involved in oxidative phosphorylation and cell adhesion. Animal studies examining haploinsufficient AD risk genes, such as vacuolar protein sorting-associated protein 35 (VPS35), sirtuin-3 (SIRT3), and PICALM, have shown that their knockout can exacerbate neurodegenerative processes by promoting amyloid production, accumulation, and inflammation. Conversely, haploinsufficiency in APOE, beta-secretase 1 (BACE1), and transmembrane protein 59 (TMEM59) was reported to confer neuroprotection by potentially slowing amyloid deposition and reducing microglial activation. Given its implications for other neurodegenerative diseases, the role of haploinsufficiency in AD requires further exploration. Modeling the mechanisms of gene knockout and monitoring their expression patterns is a promising approach to uncover AD-related pathways. However, challenges such as identifying susceptible genes, gene-environment interactions, phenotypic variability, and biomarker analysis must be addressed. Enhancing model systems through humanized animal or cell models, utilizing advanced research technologies, and integrating multi-omics data will be crucial for understanding disease pathways and developing new therapeutic strategies.

Bias analysis on socioeconomic status and lung cancer in a pooled international case-control study

Abstract Background Low socioeconomic status (SES) groups showed increased lung cancer risks even after adjustment for smoking habits and other exposures to lung carcinogens. Although several biases were often indicated and discussed, only few studies quantified the impact of potential biases. Methods We conducted a bias analysis on the association of lung cancer and SES using data from the SYNERGY project, including 12 case-control studies with 18 study centres from Europe and Canada (16,550 cases, 20,147 controls). SES in quartiles was derived from the International Socio-Economic Index of occupational status (ISEI). Odds ratios (OR) with 95% confidence intervals (CI) were estimated by logistic regression adjusting for age, study centre, and smoking. In addition, we estimated natural direct SES effects and natural indirect smoking effects by inverse odds ratio weighting. In a multiple quantitative bias analysis, we considered impacts of misclassification of smoking status, selection bias, and unmeasured mediator-outcome confounding by a protective genetic factor, and created 95% simulation intervals (SI) by bootstrap. All analyses were stratified by sex. Results Adjustment for smoking as well as natural effects estimation showed that nearly half of lung cancer risks of lower SES groups in men and up to one third in women were attributable to smoking. Consideration of all types of bias reduced lung-cancer risks in the fully adjusted logistic regression models, with the strongest impact by selection bias: For the 4th versus 1st (highest) ISEI quartile OR decreased from 1.83 (1.69-1.98 CI) to 1.50 (1.30-1.73 SI) in men, and OR 1.48 (1.27-1.72 CI) to 1.20 (0.96-1.53 SI) in women. Conclusions Smoking is the main target for prevention of lung cancer, along with occupational and environmental exposures, in particular in lower SES groups. This finding remains, though our analysis revealed reduced lung-cancer risks of lower SES groups after multiple bias adjustment. Key messages • Impact of potential biases was quantified in the association of SES and lung cancer. • Lung cancer risks were partially attributable to smoking and multiple biases.

Insights into disease resilience and longevity: Hints from COVID-19 recovered nonagenarians and centenarians

The effects of aging on the organism manifest in various ways, including profound and complex changes in functioning patterns, responses to stimuli, and regenerative capacity. Nevertheless, it is remarkable that some elderly individuals maintain their health and functionality despite advanced age, showing resilience to environmental adversities, such as SARS-CoV-2 infection. In this study, we examined a unique cohort of 100 individuals older than 90 years, including centenarians, who recovered from COVID-19 before the availability of vaccines in Brazil. We performed whole-exome analyses and identified incidental findings in four participants. These findings included pathogenic variants associated with serious conditions, such as cancer predisposition and cardiovascular diseases. Specifically, variants were found in the RYR1, DSP, BRCA2, BRCA1, and TTN genes. Also, other two individuals were homozygous for rare variants in the TYK2 gene, related to primary immunodeficiencies. The significance of these findings is underscored by the fact that, despite carrying these rare variants, these individuals surpassed 90 years of age and survived the COVID-19 pandemic. This suggests the presence of genetic protective factors that contribute to longevity and resilience. Therefore, this study provides new insights into interpreting incidental findings in long-lived populations and raises important questions for clinical practice and the genetics of longevity.

ENaC gene variants and their involvement in Covid‑19 severity.

Epidemiological studies report the association of diverse cardiovascular conditions with coronavirus disease 2019 (COVID-19), but the causality has remained to be established. Specific genetic factors and the extent to which they can explain variation in susceptibility or severity are largely elusive. The present study aimed to evaluate the link between 32 cardio-metabolic traits and COVID-19. A total of 60 participants were enrolled, who were categorized into the following 4 groups: A control group with no COVID-19 or any other underlying pathologies, a group of patients with a certain form of dyslipidemia and predisposition to atherosclerotic disease, a COVID-19 group with mild or no symptoms and a COVID-19 group with severe symptomatology hospitalized at the Intensive Care Unit of Sotiria Hospital (Athens, Greece). Demographic, clinical and laboratory data were recorded and genetic material was isolated, followed by simultaneous analysis of the genes related to dyslipidemia using a custom-made next-generation sequencing panel. In the COVID-19 group with mild or absent symptoms, the variant c.112C>T:p.P38S was detected in the sodium channel epithelial 1 subunit α (SCNN1A) gene, with a major allele frequency (Maf) of <0.01. In the COVID-19 group with severe symptoms, the variant c.786G>A:p.T262T was detected in the SCNN1B gene, which encodes for the β-subunit of the epithelial sodium channel ENaC, with a Maf <0.01. None of the two rare variants were detected in the control or dyslipidemia groups. In conclusion, the current study suggests that ENaC variants are likely associated with genetic susceptibility to COVID-19, supporting the rationale for the risk and protective genetic factors for the morbidity and mortality of COVID-19.

Higher prevalence of harbouring BCR::ABL1 in first-degree relatives of chronic myeloid leukaemia (CML) patients compared to normal population

BackgroundThe role of familial influence in chronic myeloid leukaemia (CML) occurrence is less defined. Previously, we conducted a study to determine the prevalence of harbouring BCR::ABL1 in our local adult normal population (designated as StudyN). We present our current study, which investigated the prevalence of harbouring BCR::ABL1 in the normal first-degree relatives of local CML patients (designated as StudyR). We compared and discussed the prevalence of StudyR and StudyN to assess the familial influence in CML occurrence.MethodsStudyR was a cross-sectional study using convenience sampling, recruiting first-degree relatives of local CML patients aged ≥ 18 years old without a history of haematological tumour. Real-time quantitative polymerase chain reaction standardised at the International Scale (BCR::ABL1-qPCRIS) was performed according to standard laboratory practice and the manufacturer’s protocol.ResultsA total of 96 first-degree relatives from 41 families, with a mean age of 39 and a male-to-female ratio of 0.88, were enrolled and analysed. The median number of relatives per family was 2 (range 1 to 5). Among them, 18 (19%) were parents, 39 (41%) were siblings, and 39 (41%) were offspring of the CML patients. StudyR revealed that the prevalence of harbouring BCR::ABL1 in the first-degree relatives was 4% (4/96), which was higher than the prevalence in the local normal population from StudyN, 0.5% (1/190). All four positive relatives were Chinese, with three of them being female (p > 0.05). Their mean age was 39, compared to 45 in StudyN. The BCR::ABL1–qPCRIS levels ranged between 0.0017%IS and 0.0071%IS, similar to StudyN (0.0023%IS to 0.0032%IS) and another study (0.006%IS to 0.016%IS).ConclusionOur study showed that the prevalence of harbouring BCR::ABL1 in the first-degree relatives of known CML patients was higher than the prevalence observed in the normal population. This suggests that familial influence in CML occurrence might exist but could be surpassed by other more dominant influences, such as genetic dilutional effects and protective genetic factors. The gender and ethnic association were inconsistent with CML epidemiology, suggestive of a higher familial influence in female and Chinese. Further investigation into this topic is warranted, ideally through larger studies with longer follow-up periods.

End of Life Events and Causes of Death in Danish Long-Lived Siblings: Reduced Dementia Risk Compared to Sporadic Long-Livers

Background: Better physical robustness and resilience of long-lived siblings compared to sporadic long-livers has been demonstrated in several studies. However, it is unknown whether long-lived siblings also end their lives better. Objective: To investigate end-of-life (EoL) events (dementia diagnosis, medication, hospitalizations in the last 5 years of life), causes of death, and location of death in long-lived siblings compared to matched sporadic long-livers from the Danish population. Methods: Long-lived siblings were identified through three nationwide Danish studies in which the inclusion criteria varied, but 99.5% of the families had at least two siblings surviving to age 90 + . Those who died between 2006 and 2018 were included, and randomly matched with sex, year-of-birth and age-at-death controls (i.e., sporadic long-lived controls) from the Danish population. Results: A total of 5,262 long-lived individuals were included (1,754 long-lived siblings, 3,508 controls; 63% women; median age at death 96.1). Long-lived siblings had a significantly lower risk of being diagnosed with dementia in the last years of life (p = 0.027). There was no significant difference regarding the number of prescribed drugs, hospital stays, days in hospital, and location of death. Compared to controls, long-lived siblings presented a lower risk of dying from dementia (p = 0.020) and ill-defined conditions (p = 0.030). Conclusions: In many aspects long-lived siblings end their lives similar to sporadic long-livers, with the important exception of lower dementia risk during the last 5 years of life. These results suggest that long-lived siblings are excellent candidates for identifying environmental and genetic protective factors of dementia.

Association between arachidonate lipoxygenase 15,c.-292 C > T gene polymorphism and non-cystic fibrosis bronchiectasis in children: a pilot study on the effects on airway lipoxin A4 and disease phenotype

BackgroundPersistent airway inflammation is a central feature of bronchiectasis. Arachidonate 15-lipoxygenase (ALOX-15) controls production of endogenous lipid mediators, including lipoxins that regulate airway inflammation. Mutations at various positions in ALOX-15 gene can influence airway disease development. We investigated association between ALOX-15,c.-292 C > T gene polymorphism and bronchiectasis unrelated to cystic fibrosis in Egyptian children. Also, lipoxin A4 (LXA4) level in bronchoalveolar lavage (BAL) was studied in relation to polymorphism genotypes and disease phenotypes determined by clinical, pulmonary functions, and radiological severity parameters.MethodsThis was an exploratory study that included 60 participants. Thirty children with non-cystic fibrosis bronchiectasis (NCFB) were compared with 30 age and sex-matched controls. ALOX-15,c.-292 C > T polymorphism was genotyped using TaqMan-based Real-time PCR. LXA4 was measured in BAL using ELISA method.ResultsThere was no significant difference between patients and controls regarding ALOX-15,c.-292 C > T polymorphism genotypes and alleles (OR = 1.75; 95% CI (0.53–5.7), P = 0.35) (OR = 1; 95% CI (0.48-2), p = 1). BAL LXA4 level was significantly lower in patients, median (IQR) of 576.9 (147.6–1510) ng/ml compared to controls, median (IQR) of 1675 (536.8–2542) (p = 0.002). Patients with severe bronchiectasis had a significantly lower LXA4 level (p < 0.001). There were significant correlations with exacerbations frequency (r=-0.54, p = 0.002) and FEV1% predicted (r = 0.64, p = 0.001). Heterozygous CT genotype carriers showed higher LXA4 levels compared to other genotypes(p = 0.005).ConclusionsLow airway LXA4 in children with NCFB is associated with severe disease phenotype and lung function deterioration. CT genotype of ALOX-15,c.-292 C > T polymorphism might be a protective genetic factor against bronchiectasis development and/or progression due to enhanced LXA4 production.

Cohort profile: BioMD-Y (biopsychosocial factors of major depression in youth) – a biobank study on the molecular genetics and environmental factors of depression in children and adolescents in Munich

PurposeBioMD-Y is a comprehensive biobank study of children and adolescents with major depression (MD) and their healthy peers in Germany, collecting a host of both biological and psychosocial information from...

Causal links between sedentary behavior, physical activity, and psychiatric disorders: a Mendelian randomization study

BackgroundStudies suggest a correlation between excessive sedentary behavior, insufficient physical activity, and an elevated likelihood of experiencing psychiatric disorder. Nonetheless, the precise influence of sedentary behavior and physical activity on psychiatric disorder remains uncertain. Hence, the objective of this research was to investigate the possible causal relationship between sedentary behavior, physical activity, and the susceptibility to psychiatric disorder (depression, schizophrenia and bipolar disorder), utilizing a two-sample Mendelian randomization (MR) approach.MethodsPotential genetic instruments related to sedentary leisure behaviors were identified from the UK Biobank database, specifically a summary-level genome-wide association study (GWAS) involving 422,218 individuals of European descent. The UK Biobank database also provided the GWAS data for physical activity. Primary analysis was performed using inverse variance weighting (IVW) to assess the causal relationship between sedentary behavior, physical activity, and the risk of psychiatric disorder (depression, schizophrenia and bipolar disorder). Sensitivity analysis was conducted using Cochran’s Q test, the MR–Egger intercept test, the MR-pleiotropy RESidual sum and outlier test, leave-one-out analysis, and funnel plot analysis.ResultsAccording to the IVW analysis, there was a significant association between genetically predicted leisure television watching and an increased risk of depression (odds ratio [OR] = 1.027, 95% confidence interval [CI]: 1.001–1.053; P = 0.04). The IVW analysis also indicated that there was a decreased risk of depression associated with fraction accelerations of > 425 milligravities, as measured by accelerometers (OR = 0.951, 95%CI: 0.914–0.989; P = 0.013). The other MR methods obtained consistent but non-significant results in the same direction. However, there was no evidence of a causal association between genetic liability for moderate-to-vigorous physical activity, accelerometer-assessed physical activity, computer use, or driving and the risk of depression. Furthermore, IVW analysis has also found that driving has a slight effect in reducing the risk of schizophrenia (OR = 0.092, 95%CI: 0.010–0.827; P = 0.033), while leisure television viewing has a significant protective effect against the onset of bipolar disorder (OR = 0.719, 95%CI: 0.567–0.912; P = 0.006).ConclusionThe study provides compelling evidence of a link between depression, bipolar disorder, and excessive TV watching. Furthermore, it suggests that higher accelerometer-assessed fraction accelerations of > 425 milligravities can serve as a genetic protective factor against depression. To mitigate the risk of developing depression, it is advisable to reduce sedentary activities, particularly television watching, and prioritize engaging in vigorous physical exercise.

Associative role of HLA-DRB1 as a protective factor for susceptibility and progression of Parkinson's disease: a Chinese cross-sectional and longitudinal study.

Previous genome-wide association studies investigating the relationship between the HLA-DRB1 and the risk of Parkinson's disease (PD) have shown limited racial diversity and have not explored clinical heterogeneity extensively. The study consisted of three parts: a case-control study, a cross-sectional study, and a longitudinal cohort study. The case-control study included 477 PD patients and 477 healthy controls to explore the relationship between rs660895 and PD susceptibility. The cross-sectional study utilized baseline data from 429 PD patients to examine the correlation between rs660895 and PD features. The longitudinal study included 388 PD patients who completed a 3-year follow-up to investigate the effects of rs660895 on PD progression. In the case-control study, HLA-DRB1 rs660895-G allele was associated with a decreased risk of PD in allele model (adjusted OR=0.72, p = 0.003) and dominant model (AG + GG vs. AA: adjusted OR = 0.67, p = 0.003). In the cross-sectional analysis, there was no association between rs660895 and the onset age, motor phenotype, or initial motor symptoms. In the longitudinal analysis, PD patients with the G allele exhibited a slower progression of motor symptoms (MDS-UPDRS-III total score: β = -5.42, p < 0.001, interaction ptime × genotype < 0.001) and non-motor symptoms (NMSS score: β = -4.78, p = 0.030, interaction ptime × genotype < 0.001). Our findings support HLA-DRB1 rs660895-G allele is a protective genetic factor for PD risk in Chinese population. Furthermore, we also provide new evidence for the protective effect of rs660895-G allele in PD progression.

Kharameh cohort study (KHCS) on non-communicable diseases and preliminary findings of 3-year follow-up

PurposeThe Kharameh cohort study (KHCS) is one branch of the ‘Prospective Epidemiological Research Studies in Iran’, located in the south of Iran. The enrolment phase of KHCS spanned from April...

Is the Development of Ascites in Alcoholic Liver Patients Influenced by Specific KIR/HLA Gene Profiles?

Decompensated cirrhosis is the most common cause of ascites due to hemodynamic and renal alteration by continuous fluid leakage from the hepatic sinusoids and splanchnic capillaries into the interstitial space. Then, fluid leakage exceeds lymphatic return, leading to progressive fluid accumulation directly into the peritoneal cavity. Alcohol consumption is one of the main risks of developing alcoholic cirrhosis (AC), but not all AC patients develop ascites. Avoiding the development of ascites is crucial, given that it deteriorates prognosis and increases the patient mortality patient. The innate immune system plays a crucial role in cirrhosis through natural killer cells, which are abundant in the liver. The aim of this study was to analyze the KIR/HLA-C genetic profile in AC patients with and without ascites to understand this pathology and find predictive clinical susceptibility biomarkers that can help to establish risks and prevent the development of ascites in AC patients. A total of 281 AC patients with and without ascites were analyzed and compared with 319 healthy controls. Genomic DNA was extracted from peripheral blood in all groups. A PCR-SSO assay was performed for KIR/HLA genotyping analysis. A total of 16 activating and inhibitor KIR genes and their corresponding known ligands, epitopes of HLA-C, and their genotypes were analyzed. According to our analysis, C1 epitopes were statistically significantly decreased in AC patients with and without ascites. When comparing AC patients with ascites and healthy controls, a significant decrease in C1 epitope frequency was also observed. A statistically significant decrease was also found when comparing the C1C2 genotype in AC patients without ascites with controls. In conclusion, the absence of KIR2DL2 and KIR3DL1 genes may be a predisposing factor for the development of ascites in AC patients. The KIR2DS2/KIR2DL2 may could be involved in grade I ascites development, and the presence of the C1+ epitope and the homozygous C2C2 genotype may be protective genetic factors against ascites development in AC patients.

Genetic association study of Alzheimer’s disease through whole genome tiling analysis

AbstractBackgroundNumerous GWAS studies of Alzheimer’s disease (AD) have identified over 70 AD risk variants using SNP‐based genotyping or sequencing data. Recently, a new whole‐genome tiling (WGT) representation of whole‐genome sequencing (WGS) data has been proposed to enable an innovative definition of an individual’s genome; this WGT representation can support supervised and unsupervised machine learning. In this study, we perform a new AD GWAS study on the WGT representation of the ADNI WGS data.MethodsThe detailed description, genome tiling pipeline, and a publicly available example of WGT data are available at: https://curii.co/su92l‐j7d0g‐swtofxa2rct8495. In our analysis, we first performed quality control, imputation, and one‐hot encoding of tile variants (Fig. 1). Then, for each genome tile, we used the likelihood ratio test to compare two logistic regression models to get a single p‐value, where a full model used the tile variants and covariates to predict disease status, and a null model used only covariates including age, sex, education, APOE4, and first 20 PCs. Participants included 1,504 subjects (1,032 cases and 472 controls). In comparison, set‐based GWAS analysis was performed using PLINK 1.9 on ADNI SNP‐based WGS data.Results8,560,743 tiles passed the QC process and were included in our analysis. The likelihood ratio test yielded 35,582 significant tiles with Bonferroni correction. A set‐based GWAS comparative study among all significant tiles using SNP‐based WGS data identified 1,535 sets with at least one significant SNP variant. Among 1,535 sets, 1,066 sets passed uncorrected p≤0.05; 115 sets passed p≤0.005; and 15 sets passed p≤0.0005 (Fig. 2).ConclusionsOur initial investigation of the tiling data shows that the WGT representation has promising power for identifying significant tiles that cannot be detected using the SNP representation. Complementary to the genotype values examined in traditional SNP analysis, the WGT analysis focuses on examining the haplotype variants within each tile and can capture the interaction pattern among SNPs within the haplotype. This initial AD GWAS study on WGT data demonstrates the promise of the tile representation for revealing novel genetic risk and protective factors in AD.

Association between genetic polymorphisms of leptin receptor and preeclampsia in Chinese women

Objective Leptin signaling plays an important role in regulating metabolism and reproduction. In the present study, we investigated the relationship between polymorphisms of leptin receptor (LEPR) gene A223G and A668G and preeclampsia (PE) and evaluated influences of genotypes on clinical, metabolic, and oxidative stress indices in Chinese women. Methods This is a case-control study including 322 patients with PE and 1295 healthy pregnant women. The two polymorphisms were genotyped by polymerase chain reaction-restriction fragments length polymorphism method. Clinical and biochemical parameters were analyzed. Results The frequencies of the AA + AG genotypes (28.6% vs. 36.1%) and A allele (14.9% vs. 19.8%) of LEPR A223G polymorphism, and those of the AA + AG genotypes (17.7% vs. 24.6%) and A allele (9.0% vs. 12.9%) of LEPR A668G polymorphism were significantly lower in the PE group than those in the control group. The 223A and 668A alleles were protective factors against PE in the regression model, which included age and delivery body mass index as covariates (OR = 0.684, 95% CI: 0.506–0.926, p = .014; OR = 0.650, 95% CI: 0.456–0.927, p = .017, respectively). When the 668GG/223GG combined genotype served as the reference category, the 668A/223A combined allele had further enhanced the protective effect on PE (OR = 0.558, 95% CI: 0.374–0.833, p = .004). Patients possessing the LEPR 223A allele had higher total antioxidant capacity and lower oxidative stress index (p < .05), while those with the LEPR 668A allele had higher high-density lipoprotein cholesterol levels (p = .045) compared with those carrying the corresponding GG genotype. Conclusions The 223A and 668A alleles of LEPR polymorphisms are genetic protective factors for PE in Chinese women. The two alleles may exert a beneficial effect on oxidative stress and lipid metabolism in patients.

CYP1A1 Common Gene Polymorphisms and Ischemic Stroke Risk: a Meta-Analysis and a Structural Examination

Aim: CYP1A1 is a metabolizing enzyme and key polymorphisms in its gene may contribute to the risk of ischemic stroke. This study aimed to investigate the association of the rs4646903 and rs1048943 polymorphisms of CYP1A1 with stroke risk in a meta-analysis and a bioinformatic approach. Materials & methods: An electronic search was conducted and, after the screening procedure, six eligible studies were included in the meta-analysis. Some bioinformatic tools were employed to analyze the effects of rs4646903 and rs1048943 on CYP1A1 gene function. Results: There was a significant association between rs4646903 and the reduced risk of ischemic stroke, whereas there was no significant association for rs1048943. In silico analysis showed that rs4646903 and rs1048943 polymorphisms could affect the gene expression and cofactor affinity, respectively. Conclusion: Based on these results, rs4646903 may be a protective genetic factor against ischemic stroke.

Effects of APOE ε2 allele on basal forebrain functional connectivity in mild cognitive impairment.

Basal forebrain cholinergic system (BFCS) dysfunction is associated with cognitive decline in Alzheimer's disease (AD) and mild cognitive impairment (MCI). Apolipoprotein E (APOE) ε2 is a protective genetic factor in AD and MCI, and cholinergic sprouting depends on APOE. We investigated the effect of the APOE ε2 allele on BFCS functional connectivity (FC) in cognitively normal (CN) subjects and MCI patients. We included 60 MCI patients with APOE ε3/ε3, 18 MCI patients with APOE ε2/ε3, 73 CN subjects with APOE ε3/ε3, and 36 CN subjects with APOE ε2/ε3 genotypes who had resting-state functional magnetic resonance imaging data from the Alzheimer's disease Neuroimaging Initiative. We used BFCS subregions (Ch1-3 and Ch4) as seeds and calculated the FC with other brain areas. Using a mixed-effect analysis, we explored the interaction effects of APOE ε2 allele × cognitive status on BFCS-FC. Furthermore, we examined the relationships between imaging metrics, cognitive abilities, and AD pathology markers, controlling for sex, age, and education as covariates. An interaction effect on functional connectivity was found between the right Ch4 (RCh4) and left insula (p < 0.05, corrected), and between the RCh4 and left Rolandic operculum (p < 0.05, corrected). Among all subjects and APOE ε2 carriers, RCh4-left Insula FC was associated with early tau deposition. Furthermore, no correlation was found between imaging metrics and amyloid burden. Among all subjects and APOE ε2 carriers, FC metrics were associated with cognitive performance. The APOE ε2 genotype may play a protective role during BFCS degeneration in MCI.

Genetics of autism spectrum disorders and future direction.

Autism spectrum disorders (ASDs) have been increasing in prevalence. ASD is a complex human genetic disorder with high heredity and involves interactions between genes and the environment. A significant inheritance pattern in ASD involves a rare genetic mutation; common copy number variants refer to duplication or deletion of stretches of chromosomal loci or protein-disrupting single-nucleotide variants. Haploinsufficiency is one of the more common single-gene causes of ASD, explaining at least 0.5% of cases. Epigenetic mechanisms, such as DNA methylation, act at an interface of genetic and environmental risk and protective factors. Advances in genome-wide sequencing have broadened the view of the human methylome and have revealed the organization of the human genome into large-scale methylation domains with a footprint over neurologically important genes involved in embryonic development. Psychiatric disorders, including ASD, are expected to be diagnosed based on their genetically regulated pathophysiology and to be linked to their treatment.

Cognitive Capacity Genome-Wide Polygenic Scores Identify Individuals with Slower Cognitive Decline in Aging.

The genetic protective factors for cognitive decline in aging remain unknown. Predicting an individual’s rate of cognitive decline—or with better cognitive resilience—using genetics will allow personalized intervention for cognitive enhancement and the optimal selection of target samples in clinical trials. Here, using genome-wide polygenic scores (GPS) of cognitive capacity as the genomic indicators for variations of human intelligence, we analyzed the 18-year records of cognitive and behavioral data of 8511 European-ancestry adults from the Wisconsin Longitudinal Study (WLS), specifically focusing on the cognitive assessments that were repeatedly administered to the participants with their average ages of 64.5 and 71.5. We identified a significant interaction effect between age and cognitive capacity GPS, which indicated that a higher cognitive capacity GPS significantly correlated with a slower cognitive decline in the domain of immediate memory recall (β = 1.86 × 10−1, p-value = 1.79 × 10−3). The additional phenome-wide analyses identified several associations between cognitive capacity GPSs and cognitive/behavioral phenotypes, such as similarities task (β = 1.36, 95% CI = (1.22, 1.51), p-value = 3.59 × 10−74), number series task (β = 0.94, 95% CI = (0.85, 1.04), p-value = 2.55 × 10−78), IQ scores (β = 1.42, 95% CI = (1.32, 1.51), p-value = 7.74 × 10−179), high school classrank (β = 1.86, 95% CI = (1.69, 2.02), p-value = 3.07 × 10−101), Openness from the BIG 5 personality factor (p-value = 2.19 × 10−14, β = 0.57, 95% CI = (0.42, 0.71)), and leisure activity of reading books (β = 0.50, 95% CI = (0.40, 0.60), p-value = 2.03 × 10−21), attending cultural events, such as concerts, plays, or museums (β = 0.60, 95% CI = (0.49, 0.72), p-value = 2.06 × 10−23), and watching TV (β = −0.48, 95% CI = (−0.59, −0.37), p-value = 4.16 × 10−18). As the first phenome-wide analysis of cognitive and behavioral phenotypes, this study presents the novel genetic protective effects of cognitive ability on the decline of memory recall in an aging population.

Functional associations between polymorphic regions of the human 3′IgH locus and COVID-19 disease

PurposeThe pandemic diffusion of Coronavirus Disease 2019 (COVID-19) has highlighted significant gender-related differences in disease severity. Despite several hypotheses being proposed, how the genetic background of COVID-19 patients might impact clinical outcomes remains largely unknown. MethodsWe collected blood samples from 192 COVID-19 patients (115 men, 77 women, mean age 67 ± 19 years) admitted between March and June 2020 at two different hospital centers in Italy, and determined the allelic distribution of nine Single Nucleotide Polymorphisms (SNPs), located at the 3′Regulatory Region (3′RR)-1 in the immunoglobulin (Ig) heavy chain locus, including *1 and *2 alleles of polymorphic hs1.2 enhancer region. ResultsIn COVID-19 patients, the genotyped SNPs exhibited strong Linkage Disequilibrium and produced 7 specific haplotypes, associated to different degrees of disease severity, including the occurrence of pneumonia. Additionally, the allele *2, which comprises a DNA binding site for the Estrogen receptor alpha (ERα) in the polymorphic enhancer hs1.2 of 3′RR-1, was significantly enriched in women with a less severe disease. ConclusionsThese findings document genetic variants associated to individual clinical severity of COVID-19 disease. Most specifically, a novel genetic protective factor was identified that might explain the sex-related differences in immune response to Sars-COV-2 infection in humans.