The Glucocorticoid Receptor Gene (NR3C1) 9β SNP Is Associated with Posttraumatic Stress Disorder

Genetic glucocorticoid receptor variants differ between ethnic groups but do not explain variation in age of diabetes onset, metabolic and inflammation parameters in patients with type 2 diabetes

Aims

The effect of excess glucocorticoid receptor (GR) stimulation through glucocorticoid medication or cortisol on glucose metabolism is well established. There are genetic GR variants that result in increased or decreased GR stimulation. We aimed to determine the prevalence of genetic GR variants in different ethnic groups in a cohort of patients with type 2 diabetes, and we aimed to determine their association with age of diabetes onset and metabolic and inflammation parameters.

Methods

A cross-sectional analysis was performed in a multiethnic cohort (n = 602) of patients with established type 2 diabetes. Polymorphisms in the GR gene that have previously been associated with altered glucocorticoid sensitivity (TthIIII, ER22/23EK N363S, BclI and 9β) were determined and combined into 6 haplotypes. Associations with age of diabetes onset, HbA1c, hs-CRP and lipid values were evaluated in multivariate regression models.

Results

The prevalence of the SNPs of N363S and BclI was higher in Dutch than in non-Dutch patients. We observed a lower prevalence of the SNP 9β in Dutch, South(East) Asian and Black African patients versus Turkish and Moroccan patients. We did not detect an association between SNPs and diabetes age of onset or metabolic parameters. We only found a trend for lower age of onset and higher HbA1c in patients with 1 or 2 copies of haplotype 3 (TthIIII + 9β).

Conclusions

The prevalence of genetic GR variants differs between patients of different ethnic origins. We did not find a clear association between genetic GR variants and age of diabetes onset or metabolic and inflammation parameters. This indicates that the clinical relevance of GR variants in patients with established type 2 diabetes is limited.

Implementing Core Genes and an Omnigenic Model for Behaviour Traits Prediction in Genomics

A high number of genome variants are associated with complex traits, mainly due to genome-wide association studies (GWAS). Using polygenic risk scores (PRSs) is a widely accepted method for calculating an individual's complex trait prognosis using such data. Unlike monogenic traits, the practical implementation of complex traits by applying this method still falls behind. Calculating PRSs from all GWAS data has limited practical usability in behaviour traits due to statistical noise and the small effect size from a high number of genome variants involved. From a behaviour traits perspective, complex traits are explored using the concept of core genes from an omnigenic model, aiming to employ a simplified calculation version. Simplification may reduce the accuracy compared to a complete PRS encompassing all trait-associated variants. Integrating genome data with datasets from various disciplines, such as IT and psychology, could lead to better complex trait prediction. This review elucidates the significance of clear biological pathways in understanding behaviour traits. Specifically, it highlights the essential role of genes related to hormones, enzymes, and neurotransmitters as robust core genes in shaping these traits. Significant variations in core genes are prominently observed in behaviour traits such as stress response, impulsivity, and substance use.

Assessing and Modelling of Post-Traumatic Stress Disorder Using Molecular and Functional Biomarkers

Post-traumatic stress disorder (PTSD) is a complex psychological disorder that develops following exposure to traumatic events. PTSD is influenced by catalytic factors such as dysregulated hypothalamic-pituitary-adrenal (HPA) axis, neurotransmitter imbalances, and oxidative stress. Genetic variations may act as important catalysts, impacting neurochemical signaling, synaptic plasticity, and stress response systems. Understanding the intricate gene networks and their interactions is vital for comprehending the underlying mechanisms of PTSD. Focusing on the catalytic factors of PTSD is essential because they provide valuable insights into the underlying mechanisms of the disorder. By understanding these factors and their interplay, researchers may uncover potential targets for interventions and therapies, leading to more effective and personalized treatments for individuals with PTSD. The aforementioned gene networks, composed of specific genes associated with the disorder, provide a comprehensive view of the molecular pathways and regulatory mechanisms involved in PTSD. Through this study valuable insights into the disorder's underlying mechanisms and opening avenues for effective treatments, personalized interventions, and the development of biomarkers for early detection and monitoring are provided.

NR3C1 rs6198 Variant May Be Involved in the Relationship of Graves' Disease with Stressful Events

Although stressful events are known to trigger Graves' disease (GD), the mechanisms involved in this process are not well understood. The NR3C1 gene, encoding for the glucocorticoid receptor (GR), presents single nucleotide polymorphisms (SNPs) that are associated with stress-related diseases. To investigate the relationship between NR3C1 SNPs, GD susceptibility, and clinical features, we studied 792 individuals, including 384 patients, among which 209 presented with Graves' orbitopathy (GO), and 408 paired healthy controls. Stressful life events were evaluated in a subset of 59 patients and 66 controls using the IES-R self-report questionnaire. SNPs rs104893913, rs104893909, and rs104893911 appeared at low frequencies and presented similar profiles in patients and controls. However, variant forms of rs6198 were rarer in GD patients, suggesting a protective effect. Stressful events were more common in patients than controls, and were reported to have clearly occurred immediately before the onset of GD symptoms in 23 cases. However, no association was found between these events and rs6198 genotypes or GD/GO characteristics. We suggest that the NR3C1 rs6198 polymorphism may be an important protective factor against GD, but its relationship with stressful events needs further investigation.

Hair cortisol, glucocorticoid gene receptor polymorphisms, stress, and testicular function

OBJECTIVE

Self-reported psychological stress has been associated with decreased semen quality. Cortisol levels in scalp hair (hair cortisol concentration, HCC) has emerged as a potential objective marker of psychological stress. Thus, we investigated if HCC was associated with markers of testicular function. Furthermore, we examined whether three common single nucleotide polymorphisms in the glucocorticoid-receptor gene (NR3C1, chromosome 5), potentially affecting receptor sensitivity, were associated with HCC and could influence the studied association between HCC and testicular function.

DESIGN

Cross-sectional study.

METHODS

We analysed HCC, serum-levels of reproductive hormones, semen parameters, and the three NR3C1-polymorphisms; BclI (rs41423247), Tth111I (rs10052957), and 9β (rs6198), in a population of 696 men from the general population.

RESULTS

HCC was not associated with testicular function, and adjustment for the three NR3C1-polymorphisms did not alter the results. However, HCC increased significantly with the number of Tth111I minor-alleles (T) and decreased significantly with the number of 9β minor-alleles (G).

CONCLUSION

Given previously shown associations between stress and semen quality, and that no association between HCC and self-reported stress was observed in the current study, we speculate that negative reproductive effects of stress may not be mediated directly by cortisol. This study demonstrates associations between HCC and glucocorticoid receptor gene variants indicating that these SNPs may influence systemic glucocorticoid levels, but the potential health effects of such alterations are yet unknown.

Associations of DNA methylation of HPA axis-related genes and neuroendocrine abnormalities in panic disorder

OBJECTIVE

The purpose of this study was to investigate the role of aberrant DNA methylation of hypothalamic-pituitary-adrenal (HPA) axis-related genes (CRHR1, CRHR2, CRH, FKBP5, HSP90AA1, NR3C1, and POMC) in panic disorder (PD) development. We investigated the correlation among gene methylation levels, adrenocorticotropic hormone (ACTH), cortisol, and PD severity in patients.

METHODS

We compared the methylation levels of HPA axis-related genes between 178 patients with PD and 184 healthy controls using MethylTarget. We then measured ACTH and cortisol levels using chemiluminescence. Disease severity was assessed using the Panic Disorder Severity Scale.

RESULTS

Compared with healthy controls, patients with PD displayed significantly higher levels of ACTH and cortisol, and significantly reduced methylation levels of CRHR1, FKBP5, HSP90AA1, and NR3C1 after correcting for multiple testing using the false discovery method. A significant positive correlation was observed between the methylation of CRHR1, CRHR2, and NR3C1 and ACTH levels in patients with PD, and methylation levels of CRHR1 and NR3C1 were significantly positively related to cortisol levels. In addition, a negative correlation was observed between PD severity and the methylation of CRH, CRHR1, CRHR2, and HSP90AA1.

CONCLUSION

Aberrant methylation of HPA axis-related genes may predict PD development and impact ACTH and cortisol levels.