Characterization of a glucocorticoid receptor gene (GR, NR3C1) promoter polymorphism reveals functionality and extends a haplotype with putative clinical relevance

Glucocorticoid Receptor Gene (NR3C1) Polymorphisms and Metabolic Syndrome: Insights from the Mennonite Population

The regulation of the hypothalamic-pituitary-adrenal (HPA) axis is associated with polymorphisms and the methylation degree of the glucocorticoid receptor gene (NR3C1) and is potentially involved in the development of metabolic syndrome (MetS). In order to evaluate the association between MetS with the polymorphisms, methylation, and gene expression of the NR3C1 in the genetically isolated Brazilian Mennonite population, we genotyped 20 NR3C1 polymorphisms in 74 affected (MetS) and 138 unaffected individuals without affected first-degree relatives (Co), using exome sequencing, as well as five variants from non-exonic regions, in 70 MetS and 166 Co, using mass spectrometry. The methylation levels of 11 1F CpG sites were quantified using pyrosequencing (66 MetS and 141 Co), and the NR3C1 expression was evaluated via RT-qPCR (14 MetS and 25 Co). Age, physical activity, and family environment during childhood were associated with MetS. Susceptibility to MetS, independent of these factors, was associated with homozygosity for rs10482605*C (OR = 4.74, pcorr = 0.024) and the haplotype containing TTCGTTGATT (rs3806855*T_ rs3806854*T_rs10482605*C_rs10482614*G_rs6188*T_rs258813*T_rs33944801*G_rs34176759*A_rs17209258*T_rs6196*T, OR = 4.74, pcorr = 0.048), as well as for the CCT haplotype (rs41423247*C_ rs6877893*C_rs258763*T), OR = 6.02, pcorr = 0.030), but not to the differences in methylation or gene expression. Thus, NR3C1 polymorphisms seem to modulate the susceptibility to MetS in Mennonites, independently of lifestyle and early childhood events, and their role seems to be unrelated to DNA methylation and gene expression.

Effects of prenatal exposure to the 1944-45 Dutch famine and glucocorticoid receptor polymorphisms on later life PTSD susceptibility

Background: Exposure to adversity in utero is thought to increase susceptibility to develop posttraumatic stress disorder (PTSD) following later life trauma, due to neurobiological programming effects during critical developmental periods. It remains unknown whether effects of prenatal adversity on PTSD susceptibility are modulated by genetic variations in neurobiological pathways implicated in PTSD susceptibility.Objective: We investigated whether genetic variation in the glucocorticoid receptor (GR) modulated effects of prenatal famine exposure on late adulthood PTSD symptom severity after trauma exposure in childhood and mid-to-late adulthood.Method: We included N = 439 term-born singleton adults (mean age: 72 years, 54.2% women) from the Dutch Famine Birth Cohort, born around the time of the Dutch Famine of 1944/1945, divided into exposure and control groups based on timing of the famine during gestation. Participants filled out self-report questionnaires on childhood (Childhood Trauma Questionnaire) and mid-to-late adulthood (Life Events Checklist for DSM-5) trauma, and current PTSD symptom severity (PTSD Checklist for DSM-5). GR haplotypes were determined from four functional GR single nucleotide polymorphisms (ER22/23EK, N363S, BclI and exon 9β) in previously collected DNA. Linear regression analyses were performed to investigate associations of GR haplotype and prenatal famine exposure in conjunction with later life trauma on PTSD symptom severity.Results: We observed a significant three-way interaction between the GR Bcll haplotype, famine exposure during early gestation, and adulthood trauma exposure on PTSD symptom severity in late adulthood. Only participants exposed to famine during early gestation without the GR Bcll haplotype showed a significantly stronger positive association between adulthood trauma and PTSD symptom severity than non-exposed participants, indicating increased PTSD susceptibility.Conclusions: Our results illustrate the importance of integrated approaches considering genetics and environmental contexts throughout various life periods, including the rarely investigated prenatal environment, to elucidate how PTSD susceptibility evolves throughout life.HIGHLIGHTS Adversity during pregnancy is thought to increase offspring's PTSD risk following later life trauma, but exact neurobiological mechanisms underlying this process remain unknown.We found that effects of prenatal famine exposure on PTSD symptom severity were influenced by genetic variation in the glucocorticoid receptor, which signals effects of the stress hormone cortisol.Integrated approaches considering genetics and environmental contexts throughout both early and later life are important to understand how PTSD risk evolves throughout life.

Creation of a gene expression portrait of depression and its application for identifying potential treatments

Depression is a complex mental health disorder and the goal here was to identify a consistent underlying portrait of expression that ranks all genes from most to least dysregulated and indicates direction of change relative to controls. Using large-scale neural gene expression depression datasets, a combined portrait (for men and women) was created along with one for men and one for women only. The depressed brain was characterized by a "hypo" state, that included downregulation of activity-related genes, including EGR1, FOS, and ARC, and indications of a lower brain temperature and sleep-like state. MAP kinase and BDNF pathways were enriched with overlapping genes. Expression patterns suggested decreased signaling for GABA and for neuropeptides, CRH, SST, and CCK. GWAS depression genes were among depression portrait genes and common genes of interest included SPRY2 and PSEN2. The portraits were used with the drug repurposing approach of signature matching to identify treatments that could reverse depression gene expression patterns. Exercise was identified as the top treatment for depression for the combined and male portraits. Other non-traditional treatments that scored well were: curcumin, creatine, and albiflorin. Fluoxetine scored best among typical antidepressants. The creation of the portraits of depression provides new insights into the complex landscape of depression and a novel platform for evaluating and identifying potential new treatments.

Association of Stress, Glucocorticoid Receptor, and FK506 Binding Protein Gene Polymorphisms With Internalizing Disorders Among HIV-Infected Children and Adolescents From Kampala and Masaka Districts-Uganda

Children and adolescents living with human immunodeficiency virus (CA-HIV) suffer a considerable burden of internalizing disorders (IDs; depressive and anxiety disorders). Environmental and genetic factors have been reported to influence the vulnerability to IDs in western settings; however, their role among African populations remains inadequately explored. We investigated the individual and interactive effects of stress and single-nucleotide polymorphisms within the FK506 binding protein 5 (rs1360780) and glucocorticoid receptor (rs10482605) genes on ID status in a cohort of CA-HIV in Uganda. We genotyped rs10482605 (309 cases and 315 controls) and rs1360780 (350 cases and 335 controls) among CA-HIV with and without IDs using Kompetitive Allele-Specific PCR. Socio-demographic variables, as well as allele and genotype distributions, were compared between cases and controls using chi-square tests. Genotypes were assessed for Hardy-Weinberg equilibrium. Composite indices of recent and chronic stress classes were also generated. A hierarchical cluster analysis was used to generate cutoff points within each of the indices of recent and chronic stress. Logistic regression was used to assess the association between IDs and each of recent stress, chronic stress, and the investigated genotypes. The interaction effect of chronic/recent stress on the association between each of the polymorphisms and IDs was determined using a likelihood ratio test. We observed no significant association between IDs and rs1360780 and rs10482605 polymorphisms within the FKBP5 and glucocorticoid receptor genes, respectively (P > 0.050). Severe recent stress increased the vulnerability to IDs among CA-HIV (P = 0.001). We did not observe any gene-environment effect on vulnerability to IDs in this population. These findings support the currently held opinion that polymorphisms at single genetic loci only contribute a very small effect to the genetic vulnerability to IDs.

[Corticosteroid-induced diabetes: Novelties in pathophysiology and management]

Diabetes frequently occurs during corticosteroid treatment, sometimes necessitating urgent therapeutic management, with insulin for example. Corticosteroids induce insulin resistance in the liver, adipocytes and skeletal muscle, and have direct deleterious effects on insulin secretion. The development of insulin resistance during corticosteroid treatment, and the insufficient adaptation of insulin secretion, are key elements in the pathophysiology of corticosteroid-induced diabetes. The capacity of pancreatic β-cells to increase insulin secretion in response to insulin resistance is partly genetically determined. A familial history of type 2 diabetes is, therefore, a major risk factor for diabetes development on corticosteroid treatment. Corticosteroid treatments are usually initiated at a fairly high dose, which is subsequently decreased to the lowest level sufficient to achieve disease control. Pharmacological management of diabetes is needed in patients with blood glucose levels exceeding 2.16 g/l (12 mmol/l) and insulin therapy can be started when blood glucose levels are higher than 3.6 g/l (20 mmol/l) with clinical symptoms of diabetes. Insulin can then be replaced with oral hypoglycemic compounds when both blood glucose levels and corticosteroid dose have decreased. Patient education is essential, particularly for the management of hypoglycemia when corticosteroids are withdrawn or their dose tapered.

Glucocorticoid receptor gene variants and lower expression of NR3C1 are associated with cocaine use

Animal and cross-sectional human studies suggest that chronic cocaine use is associated with altered responsivity of the hypothalamic-pituitary-adrenal axis to stress. Moreover, increased susceptibility to stress has been proposed as an important factor for development, maintenance and relapse of cocaine addiction. As the glucocorticoid receptor gene (NR3C1) mediates genomic effects of the stress hormone cortisol, we investigated NR3C1 expression and the association of NR3C1 genotypes with cocaine use, addiction and comorbid psychiatric symptoms in 126 chronic cocaine users and 98 stimulant-naïve healthy controls. A comprehensive psychiatric assessment was performed including severity of depressive symptoms and current psychological distress. Whole blood NR3C1 mRNA levels were determined and six NR3C1 polymorphisms (rs10482605, rs41423247, rs10052957, rs6189, rs56149945 and rs6198) were genotyped. Compared to controls, cocaine users showed significantly lower NR3C1 expression (P < 0.001), which was not affected by NR3C1 genotypes. In controls, rs41423247 [P < 0.01, false discovery rate (FDR)-corrected], haplotype 2 and haplotype 3 (both P < 0.05, FDR-corrected) were associated with altered NR3C1 gene expression. Haplotype 3 (including minor alleles of rs10052957 and rs41423247) was associated with an increased risk for cocaine addiction (odds ratio = 2.74, P < 0.05, uncorrected). Moreover, addicted cocaine users carrying haplotype 3 showed higher depression scores (P < 0.01, FDR-corrected) than noncarriers. Considering possible confounding effects of alcohol and/or depression, we conclude that chronic cocaine use is associated with lower NR3C1 gene expression suggesting possible direct effects of the drug on the biological adaptation of stress-related genes. Finally, we postulate that haplotype 3 of NR3C1 might serve as a potential risk factor for stimulant addiction and associated psychiatric symptoms.

Pharmacogenomic markers of glucocorticoid response in the initial phase of remission induction therapy in childhood acute lymphoblastic leukemia

Background

Response to glucocorticoid (GC) monotherapy in the initial phase of remission induction treatment in childhood acute lymphoblastic leukemia (ALL) represents important biomarker of prognosis and outcome. We aimed to study variants in several pharmacogenes (NR3C1, GSTs and ABCB1) that could contribute to improvement of GC response through personalization of GC therapy.

Methods

Retrospective study enrolling 122 ALL patients was carried out to analyze variants of NR3C1 (rs33389, rs33388 and rs6198), GSTT1 (null genotype), GSTM1 (null genotype), GSTP1 (rs1695 and rs1138272) and ABCB1 (rs1128503, rs2032582 and rs1045642) genes using PCR-based methodology. The marker of GC response was blast count per microliter of peripheral blood on treatment day 8. We carried out analysis in which cut-off value for GC response was 1000 (according to Berlin-Frankfurt-Munster [BFM] protocol), as well as 100 or 0 blasts per microliter.

Results

Carriers of rare NR3C1 rs6198 GG genotype were more likely to have blast count over 1000, than the non-carriers (p = 0.030). NR3C1 CAA (rs33389-rs33388-rs6198) haplotype was associated with blast number below 1000 (p = 0.030). GSTP1 GC haplotype carriers were more likely to have blast number below 1000 (p = 0.036), below 100 (p = 0.028) and to be blast negative (p = 0.054), while GSTP1 GT haplotype and rs1138272 T allele carriers were more likely to be blasts positive (p = 0.034 and p = 0.024, respectively). ABCB1 CGT (rs1128503-rs2032582-rs1045642) haplotype carriers were more likely to be blast positive (p = 0.018).

Conclusions

Our results have shown that NR3C1 rs6198 variant and GSTP1 rs1695-rs1138272 haplotype are the most promising pharmacogenomic markers of GC response in ALL patients.

Genetic variation in the glucocorticoid receptor and psychopathology after dexamethasone administration in cardiac surgery patients

The glucocorticoid receptor (GR) agonist dexamethasone is frequently used for its anti-inflammatory properties. We recently showed that a single high-dose of dexamethasone had long-lasting protective effects on the development of psychopathology after cardiac surgery and postoperative intensive care unit stay. In this study, we investigated whether common genetic variation in the hypothalamic-pituitary-adrenal (HPA)-axis would influence the susceptibility for PTSD and depression after dexamethasone administration. Participants (n = 996) of the Dexamethasone for Cardiac Surgery (DECS) randomized clinical trial were followed after receiving a single high intraoperative dose of dexamethasone (1 mg/kg), a GR agonist, or placebo. PTSD and depressive symptoms were assessed up to four years after cardiac surgery. We focused primarily on five common single nucleotide polymorphisms (SNPs) in the glucocorticoid receptor (GR). Secondarily, we comprehensively assessed common genetic variation in the FK506 binding protein (FKBP5) and the mineralocorticoid receptor (MR). The protective effects of dexamethasone on postoperative PTSD symptoms were dependent on the GR polymorphisms rs41423247 (p = .009), rs10052957 (p = .003), and rs6189 (p = .002), but not on rs6195 (p = .025) or rs6198, (p = .026) after Bonferroni correction. No genotype-dependent effects were found for postoperative depressive symptoms. Also, no associations of FKBP5 and MR polymorphisms were found on PTSD and depression outcomes. Protective effects of dexamethasone on PTSD symptoms after cardiac surgery and ICU stay seem to depend on common genetic variation in its target receptor, the GR. These effects indicate that pre-operative genetic screening could potentially help in stratifying patients for their vulnerability for developing PTSD symptoms after surgery.

Hypothalamic-pituitary-adrenal axis variants and childhood trauma influence anxiety sensitivity in South African adolescents

Anxiety sensitivity (AS) is characterised by the fear of anxiety-related symptoms and is a risk factor for the development of anxiety-related disorders. We examined whether genetic variation in three stress response genes, CRHR1, NR3C1, and FKBP5, interact with childhood trauma (CT) to predict AS in South African adolescents. Xhosa (n = 634) and Coloured (n = 317) students completed self-report measures of AS and CT, and a total of eighteen polymorphisms within CRHR1, NR3C1, and FKBP5 were genotyped. Differences in AS based on genetic variation and CT were analysed within population and gender groups using multiple linear regression. Associations were found between AS and FKBP5 rs9296158 (p = 0.025) and rs737054 (p = 0.045) in Coloured males. Analysis of gene x CT interactions indicated that NR3C1 rs190488 CC-genotype, NR3C1 rs10482605 G-allele addition, and FKBP5 rs3800373 C-allele addition protect against AS with increasing CT in Xhosa females (p = 0.009), Xhosa males (p = 0.036) and Coloured males (p = 0.049), respectively. We identified two different protective single nucleotide polymorphism (SNP) combinations in a four-SNP CRHR1 haplotype in Coloured males. An analysis of the interaction between CT and a six-SNP FKBP5 haplotype in Coloured males revealed both protective and risk allelic combinations. Our results provide evidence for the influence of both genetic variation in CRHR1, NR3C1 and FKBP5, as well as CT x SNP interactions, on AS in South African adolescents. This study reinforces the importance of examining the influence of gene-environment (G X E) interactions within gender and population groups.

Glucocorticoid receptor variants in childhood attention-deficit/hyperactivity disorder and comorbid psychiatric disorders

Stress results in a variety of neuroendocrine, immune and behavioral responses and represents a risk factor for many disorders. Following exposure to stress, glucocorticoids are secreted from the adrenal cortex and act via the ligand-activated glucocorticoid receptor (GR). Several polymorphisms of the GR-encoding gene NR3C1 have been described and functionally investigated. However, the impact of these variants on complex diseases such as Attention-Deficit/Hyperactivity Disorder (ADHD) is still unclear. In this study, 251 children with ADHD, 19 affected and 35 unaffected siblings, and their parents were included in a family-based association study assessing seven common variants of NR3C1 (TthIIII_rs10052957; NR3C1-I_rs10482605; ER22/23EK_rs6189/rs6190; N363S_rs56149945; BclI_rs41423247; GR-9beta_rs6198). A four-marker haplotype (TthIIII-NR3C1-I-ER22/23EK) was nominally associated with ADHD. In addition, in index children with ADHD, associations with comorbid disorders, inattentive and hyperactive-impulsive symptoms were explored. N363S minor allele carriers were more likely to show comorbid conduct disorder (CD). In our study, NR3C1 variants moderately affected ADHD and had a significant effect on comorbid CD. Therefore, NR3C1 as an important gene of the hypothalamic-pituitary-adrenal axis seems to be particularly relevant for the pathophysiology of ADHD combined with comorbid CD. For a deeper understanding, investigations in larger samples of healthy, ADHD and CD individuals are warranted.

The Association of Neighborhood Gene-Environment Susceptibility with Cortisol and Blood Pressure in African-American Adults

BACKGROUND

African-American adults are disproportionately affected by stress-related chronic conditions like high blood pressure (BP), and both environmental stress and genetic risk may play a role in its development.

PURPOSE

This study tested whether the dual risk of low neighborhood socioeconomic status (SES) and glucocorticoid genetic sensitivity interacted to predict waking cortisol and BP.

METHODS

Cross-sectional waking cortisol and BP were collected from 208 African-American adults who were participating in a follow-up visit as part of the Positive Action for Today's Health trial. Three single-nucleotide polymorphisms were genotyped, salivary cortisol samples were collected, and neighborhood SES was calculated using 2010 Census data.

RESULTS

The sample was mostly female (65 %), with weight classified as overweight or obese (M BMI = 32.74, SD = 8.88) and a mean age of 55.64 (SD = 15.21). The gene-by-neighborhood SES interaction predicted cortisol (B = 0.235, p = .001, r (2) = .036), but not BP. For adults with high genetic sensitivity, waking cortisol was lower with lower SES but higher with higher SES (B = 0.87). Lower neighborhood SES was also related to higher systolic BP (B = -0.794, p = .028).

CONCLUSIONS

Findings demonstrated an interaction whereby African-American adults with high genetic sensitivity had high levels of waking cortisol with higher neighborhood SES, and low levels with lower neighborhood SES. This moderation effect is consistent with a differential susceptibility gene-environment pattern, rather than a dual-risk pattern. These findings contribute to a growing body of evidence that demonstrates the importance of investigating complex gene-environment relations in order to better understand stress-related health disparities.

Glucocorticoid receptor gene modulates severity of depression in women with crack cocaine addiction

Crack cocaine addicted inpatients that present more severe withdrawal symptoms also exhibit higher rates of depressive symptoms. There is strong evidence that the identification of genetic variants in depression is potentialized when reducing phenotypic heterogeneity by studying selected groups. Since depression has been associated to dysregulation of the hypothalamic-pituitary-adrenal axis, this study evaluated the effects of SNPs in stress-related genes on depressive symptoms of crack cocaine addicts at early abstinence and over the detoxification treatment (4th, 11th and 18th day post admission). Also, the role of these SNPs on the re-hospitalization rates after 2.5 years of follow-up was studied. One hundred eight-two women were enrolled and eight SNPs in four genes (NR3C2, NR3C1, FKBP5 and CRHR1) were genotyped. A significant main effect of NR3C1-rs41423247 was found, where the C minor allele increased depressive symptoms at early abstinence. This effect remained significant after 10,000 permutations to account for multiple SNPs tested (P=0.0077). There was no effect of rs41423247 on the course of detoxification treatment, but a slight effect of rs41423247 at late abstinence was detected (P=0.0463). This analysis suggests that the presence of at least one C allele is worse at early abstinence, while only CC genotype appears to increase depressive symptoms at late abstinence. Also, a slight effect of rs41423247 C minor allele increasing the number of re-hospitalizations after 2.5 years was found (P=0.0413). These findings are in agreement with previous studies reporting an influence of rs41423247 on sensitivity to glucocorticoids and further elucidate its resulting effects on depressive-related traits.

Interplay between stress response genes associated with attention-deficit hyperactivity disorder and brain volume

The glucocorticoid receptor plays a pivotal role in the brain's response to stress; a haplotype of functional polymorphisms in the NR3C1 gene encoding this receptor has been associated with attention-deficit hyperactivity disorder (ADHD). The serotonin transporter (5-HTT) gene polymorphism 5-HTTLPR is known to influence the relation between stress exposure and ADHD severity, which may be partly because of its reported effects on glucocorticoid levels. We therefore investigated if NR3C1 moderates the relation of stress exposure with ADHD severity and brain structure, and the potential role of 5-HTTLPR. Neuroimaging, genetic and stress exposure questionnaire data were available for 539 adolescents and young adults participating in the multicenter ADHD cohort study NeuroIMAGE (average age: 17.2 years). We estimated the effects of genetic variation in NR3C1 and 5-HTT, stress exposure and their interactions on ADHD symptom count and gray matter volume. We found that individuals carrying the ADHD risk haplotype of NR3C1 showed significantly more positive relation between stress exposure and ADHD severity than non-carriers. This gene-environment interaction was significantly stronger for 5-HTTLPR L-allele homozygotes than for S-allele carriers. These two- and three-way interactions were reflected in the gray matter volume of the cerebellum, parahippocampal gyrus, intracalcarine cortex and angular gyrus. Our findings illustrate how genetic variation in the stress response pathway may influence the effects of stress exposure on ADHD severity and brain structure. The reported interplay between NR3C1 and 5-HTT may further explain some of the heterogeneity between studies regarding the role of these genes and hypothalamic-pituitary-adrenal axis activity in ADHD.

GLUCOCORTICOID RECEPTOR-RELATED GENES: GENOTYPE AND BRAIN GENE EXPRESSION RELATIONSHIPS TO SUICIDE AND MAJOR DEPRESSIVE DISORDER

INTRODUCTION

We tested the relationship between genotype, gene expression and suicidal behavior and major depressive disorder (MDD) in live subjects and postmortem samples for three genes, associated with the hypothalamic-pituitary-adrenal axis, suicidal behavior, and MDD; FK506-binding protein 5 (FKBP5), Spindle and kinetochore-associated protein 2 (SKA2), and Glucocorticoid Receptor (NR3C1).

MATERIALS AND METHODS

Single-nucleotide polymorphisms (SNPs) and haplotypes were tested for association with suicidal behavior and MDD in a live (N = 277) and a postmortem sample (N = 209). RNA-seq was used to examine gene and isoform-level brain expression postmortem (Brodmann Area 9; N = 59). Expression quantitative trait loci (eQTL) relationships were examined using a public database (UK Brain Expression Consortium).

RESULTS

We identified a haplotype within the FKBP5 gene, present in 47% of the live subjects, which was associated with increased risk of suicide attempt (OR = 1.58, t = 6.03, P = .014). Six SNPs on this gene, three SNPs on SKA2, and one near NR3C1 showed before-adjustment association with attempted suicide, and two SNPs of SKA2 with suicide death, but none stayed significant after adjustment for multiple testing. Only the SKA2 SNPs were related to expression in the prefrontal cortex (pFCTX). One NR3C1 transcript had lower expression in suicide relative to nonsuicide sudden death cases (b = -0.48, SE = 0.12, t = -4.02, adjusted P = .004).

CONCLUSION

We have identified an association of FKBP5 haplotype with risk of suicide attempt and found an association between suicide and altered NR3C1 gene expression in the pFCTX. Our findings further implicate hypothalamic pituitary axis dysfunction in suicidal behavior.

Early-Life Adversity Interacts with FKBP5 Genotypes: Altered Working Memory and Cardiac Stress Reactivity in the Oklahoma Family Health Patterns Project

Exposure to stress during critical periods of development can have adverse effects on adult health behaviors, and genetic vulnerabilities may enhance these stress effects. We carried out an exploratory examination of psychological, physiological, and behavioral characteristics of 252 healthy young adults for the impact of early-life adversity (ELA) in relation to the G-to-A single nucleotide polymorphism (SNP), rs9296158, of the FKBP5 gene. FKBP5 is a molecular cochaperone that contributes to the functional status of the glucocorticoid receptor (GR) and to the quality of corticosteroid signaling. FKBP5 expression is upregulated by cortisol exposure during stressful episodes, with greater upregulation seen in A-allele carriers. As such, FKBP5 expression and GR function may be environmentally sensitive in A-allele carriers and therefore suitable for the study of gene-by-environment (G × E) interactions. Compared with FKBP5, GG homozygotes (N=118), A-allele carriers (N = 132) without psychiatric morbidity had progressively worse performance on the Stroop color-word task with increasing levels of ELA exposure (Genotype × ELA, F=5.14, P=0.007), indicating a G × E interaction on working memory in early adulthood. In addition, heart rate response to mental stress was diminished overall in AA/AG-allele carriers (F=5.15, P=0.024). Diminished working memory and attenuated autonomic responses to stress are both associated with risk for alcoholism and other substance use disorders. The present data suggest that FKBP5 in the GR pathway may be a point of vulnerability to ELA, as seen in this group of non-traumatized young adults. FKBP5 is accordingly a potential target for more extensive studies of the impact of ELA on health and health behaviors in adulthood.

Developmental mediation of genetic variation in response to the Fast Track prevention program

We conducted a developmental analysis of genetic moderation of the effect of the Fast Track intervention on adult externalizing psychopathology. The Fast Track intervention enrolled 891 children at high risk to develop externalizing behavior problems when they were in kindergarten. Half of the enrolled children were randomly assigned to receive 10 years of treatment, with a range of services and resources provided to the children and their families, and the other half to usual care (controls). We previously showed that the effect of the Fast Track intervention on participants' risk of externalizing psychopathology at age 25 years was moderated by a variant in the glucocorticoid receptor gene. Children who carried copies of the A allele of the single nucleotide polymorphism rs10482672 had the highest risk of externalizing psychopathology if they were in the control arm of the trial and the lowest risk of externalizing psychopathology if they were in the treatment arm. In this study, we test a developmental hypothesis about the origins of this for better and for worse Gene × Intervention interaction (G × I): that the observed G × I effect on adult psychopathology is mediated by the proximal impact of intervention on childhood externalizing problems and adolescent substance use and delinquency. We analyzed longitudinal data tracking the 270 European American children in the Fast Track randomized control trial with available genetic information (129 intervention children, 141 control group peers, 69% male) from kindergarten through age 25 years. Results show that the same pattern of for better and for worse susceptibility to intervention observed at the age 25 follow-up was evident already during childhood. At the elementary school follow-ups and at the middle/high school follow-ups, rs10482672 predicted better adjustment among children receiving the Fast Track intervention and worse adjustment among children in the control condition. In turn, these proximal G × I effects early in development mediated the ultimate G × I effect on externalizing psychopathology at age 25 years. We discuss the contribution of these findings to the growing literature on genetic susceptibility to environmental intervention.

The cardiovascular and hypothalamus-pituitary-adrenal axis response to stress is controlled by glucocorticoid receptor sequence variants and promoter methylation

BACKGROUND

Gender, genetic makeup, and prior experience interact to determine physiological responses to an external perceived stressor. Here, we investigated the contribution of both genetic variants and promoter methylation of the NR3C1 (glucocorticoid receptor) gene to the cardiovascular and hypothalamus-pituitary-adrenal (HPA) axis response to the socially evaluated cold pressor test (seCPT).

RESULTS

Two hundred thirty-two healthy participants were recruited and underwent the experiment. They were randomly assigned to either the seCPT group (cold water) or a control group (warm water). The seCPT group had a clear stress reaction; salivary cortisol levels and peak systolic and diastolic blood pressure all increased significantly compared to the control group. GR genotype (TthIIII, NR3C1-I, 1H, E22E, R23K, BclI and 9beta) and methylation data were obtained from 218 participants. Haplotypes were built from the GR genotypes, and haplotype 2 (minor allele of BclI) carriers had a higher cortisol response to the seCPT in comparison to non-carriers (20.77 ± 13.22; 14.99 ± 8.42; p = 0.034), as well as independently of the experimental manipulation, higher baseline heart rate (72.44 ± 10.99; 68.74 ± 9.79; p = 0.022) and blood pressure (115.81 ± 10.47; 111.61 ± 10.74; p = 0.048). Average methylation levels throughout promoter 1F and 1H were low (2.76 and 1.69 %, respectively), but there was a strong correlation between individual CpGs and the distance separating them (Pearson's correlation r = 0.725, p = 3.03 × 10(-26)). Higher promoter-wide methylation levels were associated with decreased baseline blood pressure, and when incorporated into a linear mixed effect model significantly predicted lower systolic and diastolic blood pressure evolution over time in response to the experimental manipulation. The underlying genotype significantly predicted methylation levels; particularly, the homozygous BclI minor allele was associated with higher methylation in promoter 1H (p = 0.042).

CONCLUSIONS

This is one of the first studies linking epigenetic modifications of the GR promoter, receptor genotype and physiological measures of the stress response. At baseline, there were clear genetic and epigenetic effects on blood pressure. The seCPT induced a strong cardiovascular and HPA axis response, and both systems were affected by the functional genetic variants, although methylation also predicted blood pressure reactivity. The return to baseline was predominantly influenced by the genomic sequence. Overall, the physiological response to the seCPT is controlled by an exquisite mix of genetic and epigenetic factors.

Single nucleotide polymorphisms in non-coding region of the glucocorticoid receptor gene and prednisone response in childhood acute lymphoblastic leukemia

Poor prednisone response predicts an inferior outcome in pediatric acute lymphoblastic leukemia (ALL) in Berlin-Frankfurt-Münster (BFM) treatment protocols. Here, we investigated five single nucleotide polymorphisms (SNPs) in both the coding and non-coding regions of the glucocorticoid receptor (GR) gene, and analyzed their association with prednisone responsiveness in vivo in 63 pediatric patients with ALL in China. Of the five SNPs, the rs41423247 and rs7701443 polymorphisms were significantly associated with prednisone response at the allelic level (rs41423247 odds ratio [OR] = 9.58; 95% confidence interval [CI]: 1.23-74.21; p = 0.01; rs7701443 OR = 3.12; 95% CI: 1.08-9; p = 0.02). Two polymorphisms (rs6189/6190 and rs6198) were not observed in the study cohort. Haplotypes composed of CCC alleles and TCG alleles at three loci (rs7701443, Tth111I and BclI) were both associated with prednisone response (p = 0.013; p = 0.028). Our results suggested that polymorphisms in the non-coding region of the GR gene were associated with prednisone response in vivo in pediatric ALL in Han Chinese.

Can Genetics Predict Response to Complex Behavioral Interventions? Evidence from a Genetic Analysis of the Fast Track Randomized Control Trial

Early interventions are a preferred method for addressing behavioral problems in high-risk children, but often have only modest effects. Identifying sources of variation in intervention effects can suggest means to improve efficiency. One potential source of such variation is the genome. We conducted a genetic analysis of the Fast Track randomized control trial, a 10-year-long intervention to prevent high-risk kindergarteners from developing adult externalizing problems including substance abuse and antisocial behavior. We tested whether variants of the glucocorticoid receptor gene NR3C1 were associated with differences in response to the Fast Track intervention. We found that in European-American children, a variant of NR3C1 identified by the single-nucleotide polymorphism rs10482672 was associated with increased risk for externalizing psychopathology in control group children and decreased risk for externalizing psychopathology in intervention group children. Variation in NR3C1 measured in this study was not associated with differential intervention response in African-American children. We discuss implications for efforts to prevent externalizing problems in high-risk children and for public policy in the genomic era.

Glucocorticoid receptor polymorphisms and haplotypes and their expression in health and disease

Cortisol is involved in many physiological processes, including immunosuppressive and anti-inflammatory actions, and therefore cortisol and its synthetic analogs are widely used to treat a large number of diseases. In glucocorticoid treatment, a large variability of clinical responses is observed. This variability may, in part, be ascribed to genetic variation in the glucocorticoid receptor (GR) gene. In this review we present a catalogue of the various single nucleotide polymorphisms (SNPs) in the glucocorticoid receptor gene and their consequences for human health and disease. Many different GR SNP association studies have been described. However, most studies come down to only a few SNPs reported with different annotations. In this review we clarified these different annotations to uniform names. Most associations between GR SNPs and phenotype have been found in body composition, metabolism, the cardiovascular system, the immune system and psychiatric illnesses. However, many associations have not been replicated (yet), and future replication studies and meta-analyses are needed. There is a substantial body of evidence for GR SNPs to have effects on clinical phenotype. However, as most SNP frequencies are low and their variation is within the range of the general population, the impact of a single SNP for health and disease in the general population is probably modest. However, in-depth studying of the molecular mechanisms of repeatedly observed clinical associations could lead to new possibilities for drug development. In particular the development of selective glucocorticoid receptor modulators holds promise.

The relationship between glucocorticoid receptor polymorphisms, stressful life events, social support, and post-traumatic stress disorder

BACKGROUND

It is debatable whether or not glucocorticoid receptor (GR) polymorphisms moderate susceptibility to PTSD. Our objective was to examine the effects of stressful life events, social support, GR genotypes, and gene-environment interactions on the etiology of PTSD.

METHODS

Three tag single nucleotide polymorphisms, trauma events, stressful life events, and social support were assessed in 460 patients with PTSD and 1158 control subjects from a Chinese Han population. Gene-environment interactions were analyzed by generalized multifactor dimensionality reduction (GMDR).

RESULTS

Variation in GR at rs41423247 and rs258747, stressful life events, social support, and the number of traumatic events were each separately associated with the risk for PTSD. A gene-environment interaction among the polymorphisms, rs41423247 and rs258747, the number of traumatic events, stressful life events, and social support resulted in an increased risk for PTSD. High-risk individuals (a large number of traumatic events, G allele of rs258747 and rs41423247, high level stressful life events, and low social support) had a 3.26-fold increased risk of developing PTSD compared to low-risk individuals. The association was statistically significant in the sub-groups with and without childhood trauma.

CONCLUSIONS

Our data support the notion that stressful life events, the number of trauma events, and social support may play a contributing role in the risk for PTSD by interacting with GR gene polymorphisms.

Hypothesis of the neuroendocrine cortisol pathway gene role in the comorbidity of depression, type 2 diabetes, and metabolic syndrome

Depression, type 2 diabetes (T2D), and metabolic syndrome (MetS) are often comorbid. Depression per se increases the risk for T2D by 60%. This risk is not accounted for by the use of antidepressant therapy. Stress causes hyperactivation of the hypothalamic–pituitary–adrenal (HPA) axis, by triggering the hypothalamic corticotropin-releasing hormone (CRH) secretion, which stimulates the anterior pituitary to release the adrenocorticotropin hormone (ACTH), which causes the adrenal secretion of cortisol. Depression is associated with an increased level of cortisol, and CRH and ACTH at inappropriately “normal” levels, that is too high compared to their expected lower levels due to cortisol negative feedback. T2D and MetS are also associated with hypercortisolism. High levels of cortisol can impair mood as well as cause hyperglycemia and insulin resistance and other traits typical of T2D and MetS. We hypothesize that HPA axis hyperactivation may be due to variants in the genes of the CRH receptors (CRHR1, CRHR2), corticotropin receptors (or melanocortin receptors, MC1R-MC5R), glucocorticoid receptor (NR3C1), mineralocorticoid receptor (NR3C2), and of the FK506 binding protein 51 (FKBP5), and that these variants may be partially responsible for the clinical association of depression, T2D and MetS. In this review, we will focus on the correlation of stress, HPA axis hyperactivation, and the possible genetic role of the CRHR1, CRHR2, MCR1–5, NR3C1, and NR3C2 receptors and FKBP5 in the susceptibility to the comorbidity of depression, T2D, and MetS. New studies are needed to confirm the hypothesized role of these genes in the clinical association of depression, T2D, and MetS.

HPA axis genetic variation, cortisol and psychosis in major depression

Genetic variation underlying hypothalamic pituitary adrenal (HPA) axis overactivity in healthy controls (HCs) and patients with severe forms of major depression has not been well explored, but could explain risk for cortisol dysregulation. In total, 95 participants were studied: 40 patients with psychotic major depression (PMD); 26 patients with non-psychotic major depression (NPMD); and 29 HCs. Collection of genetic material was added one third of the way into a larger study on cortisol, cognition and psychosis in major depression. Subjects were assessed using the Brief Psychiatric Rating Scale, the Hamilton Depression Rating Scale and the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders. Blood was collected hourly for determination of cortisol from 1800 to 0900 h and for the assessment of alleles for six genes involved in HPA axis regulation. Two of the six genes contributed significantly to cortisol levels, psychosis measures or depression severity. After accounting for age, depression and psychosis, and medication status, only allelic variation for the glucocorticoid receptor (GR) gene accounted for a significant variance for mean cortisol levels from 1800 to 0100 h (r(2)=0.288) and from 0100 to 0900 h (r(2)=0.171). In addition, GR and corticotropin-releasing hormone receptor 1 (CRHR1) genotypes contributed significantly to psychosis measures and CRHR1 contributed significantly to depression severity rating.

Genetic mapping with multiple levels of phenotypic information reveals determinants of lymphocyte glucocorticoid sensitivity

Clinical response to glucocorticoids, steroid hormones widely used as pharmaceuticals, varies extensively in that many individuals (∼30%) show a weak response to treatment. Although little is known about the molecular basis of this variation, regulatory polymorphisms are likely to play a key role given that glucocorticoids act largely through activation of a transcription factor, the glucocorticoid receptor. In an effort to characterize the molecular basis of variation in glucocorticoid sensitivity, we measured in vitro lymphocyte glucocorticoid sensitivity and transcriptome-wide response to glucocorticoids in peripheral-blood mononuclear cells from African American healthy donors. We found that variation in lymphocyte glucocorticoid sensitivity was correlated with transcriptional response at 27 genes (false-discovery rate < 0.1). Furthermore, a genome-wide association scan revealed a quantitative trait locus (QTL) for lymphocyte glucocorticoid sensitivity (rs11129354, p = 4 × 10(-8)); it was also associated with transcriptional response at multiple genes, including many (14/27) where transcriptional response was correlated with lymphocyte glucocorticoid sensitivity. Using allelic-imbalance assays, we show that this QTL is a glucocorticoid-dependent cis-regulatory polymorphism for RBMS3, which encodes an RNA-binding protein known as a tumor suppressor. We found that siRNA-mediated knockdown of RBMS3 expression increased cellular proliferation in PBMCs, consistent with the role of the gene as a negative regulator of proliferation. We propose that differences in lymphocyte glucocorticoid sensitivity reflect variation in transcriptional response, which is influenced by a glucocorticoid-dependent regulatory polymorphism that acts in cis relative to RBMS3 and in trans to affect the transcriptional response of multiple distant genes.

A neurogenetics approach to understanding individual differences in brain, behavior, and risk for psychopathology

Neurogenetics research has begun to advance our understanding of how genetic variation gives rise to individual differences in brain function, which, in turn, shapes behavior and risk for psychopathology. Despite these advancements, neurogenetics research is currently confronted by three major challenges: (1) conducting research on individual variables with small effects, (2) absence of detailed mechanisms, and (3) a need to translate findings toward greater clinical relevance. In this review, we showcase techniques and developments that address these challenges and highlight the benefits of a neurogenetics approach to understanding brain, behavior and psychopathology. To address the challenge of small effects, we explore approaches including incorporating the environment, modeling epistatic relationships and using multilocus profiles. To address the challenge of mechanism, we explore how non-human animal research, epigenetics research and genome-wide association studies can inform our mechanistic understanding of behaviorally relevant brain function. Finally, to address the challenge of clinical relevance, we examine how neurogenetics research can identify novel therapeutic targets and for whom treatments work best. By addressing these challenges, neurogenetics research is poised to exponentially increase our understanding of how genetic variation interacts with the environment to shape the brain, behavior and risk for psychopathology.

Common variants of the mineralocorticoid and glucocorticoid receptor genes may contribute to pregnancy-related anxiety: a pilot study

The hypothalamic-pituitary-adrenal (HPA) axis overactivity is thought to contribute to increased vulnerability to maternal stress. We hypothesize that functionally relevant polymorphic variants of the glucocorticoid (NR3C1) and mineralocorticoid (NR3C2) receptor genes mediating biological effects of cortisol, a major stress hormone, could also modulate the capacity to cope with pregnancy-related anxiety. Genomic DNA from the blood of 42 women with pregnancy-related anxiety and 42 age-matched women with normal pregnancy (5–6th months of gestation) were genotyped for markers rs6195 and rs10482605 of NR3C1 and two NR3C2 polymorphisms (rs5522 and rs2070951) using a Taqman allele discrimination assay. Serum total cortisol was measured using an ELISA technique. The allele Ser363 of rs6195 (the N363S polymorphism of NR3C1) was found to be associated with a higher risk of maternal stress (odds ratio (OR)=5.27; P=0.001). For NR3C2, the allele Val180 of rs5522 (I180V) also showed association with increased risk of neonatal stress (OR=1.97; P=0.038). Both predisposing gene variants were also associated with significantly elevated levels of cortisol in normally pregnant women and females with pregnancy-related anxiety. Our results suggest that pregnancy-related anxiety can be modulated by variants of NR3C1 and NR3C2 associated with increased basal cortisol levels. Thus, our findings provide evidence in support of the suggestion that elevated cortisol levels and HPA axis hyperactivity are implicated in pregnancy-related anxiety.

Interaction of the cholinergic system and the hypothalamic-pituitary-adrenal axis as a risk factor for depression: evidence from a genetic association study

Chronic stress and related disruption of hypothalamic-pituitary-adrenal axis reactivity is a known risk factor for depression. Besides its effects on glucocorticoids, stress also impacts the cholinergic system. Therefore, the interaction of two polymorphisms, one on the cholinergic CHRNA4 receptor gene and one on the glucocorticoid receptor gene (NR3C1), on depression was investigated. In a sample of 800 healthy participants, we genotyped for the BCL1 rs41423247 and the CHRNA4 rs1044396 single-nucleotide polymorphisms and assessed depressiveness by means of the Beck Depression Inventory. We identified a significant epistasis effect BCL1 by CHRNA4 showing that carriers of the CC genotype at the BCL1 locus who were also homozygous for the T allele at the CHRNA4 locus had the highest depression scores. This is the first evidence from molecular genetics to show that the hypothalamic-pituitary-adrenal axis and the cholinergic system--both involved in stress reactivity--represent a combined risk factor for depression.

Epigenetic and genetic factors predict women's salivary cortisol following a threat to the social self

Evidence suggests that the reactivity of the Hypothalamus-Pituitary-Adrenal axis (HPAA) is modulated by both genetic and environmental variables. Of special interest are the underlying molecular mechanisms driving gender differences to psychosocial stressors. Epigenetic mechanisms that sculpt the genome are ideal candidates for mediating the effects of signals on the HPAA. In the current study, we analyzed by pyrosequencing, bisulfite-treated buccal DNA from male and female university students who participated in the Trier Social Stress Test (TSST). A linear regression model was used to ascertain the effects of sex, CpG methylation and genes on stress response. Total cortisol output (area under the curve, AUC) was significantly predicted by glucocorticoid receptor (NR3C1) exon 1F methylation (averaged across 39 CpG sites) solely in female subjects. A single CpG site located in the exon 1F noncanonical nerve growth factor-inducible protein A (NGFI-A) transcription factor was a highly significant predictor of AUC in female subjects. Additionally, variations in the estrogen receptor alpha (ESR1) and the serotonin transporter promoter (5-HTTLPR) genes were independent additive predictors of AUC. The full model accounted for half of the variance (50.06%) in total cortisol output. Notably, this is the first demonstration that epigenetic changes at the GR exon 1F correlate with HPAA reactivity. These findings have important implications for understanding the molecular mechanisms underlying gender differences in stress-related disorders and underscore the unique value of modeling both epigenetic and genetic information in conferring vulnerability to stress.

Inter-ethnic differences in lymphocyte sensitivity to glucocorticoids reflect variation in transcriptional response

Glucocorticoids (GCs) are steroid hormones widely used as pharmaceutical interventions, which act mainly by regulating gene expression levels. A large fraction of patients (~30%), especially those of African descent, show a weak response to treatment. To interrogate the contribution of variable transcriptional response to inter-ethnic differences, we measured in vitro lymphocyte GC sensitivity (LGS) and transcriptome-wide response to GCs in peripheral blood mononuclear cells (PBMCs) from African-American and European-American healthy donors. We found that transcriptional response after 8hrs treatment was significantly correlated with variation in LGS within and between populations. We found that NFKB1, a gene previously found to predict LGS within populations, was more strongly down-regulated in European-Americans on average. NFKB1 could not completely explain population differences, however, and we found an additional 177 genes with population differences in the average log₂ fold change (FDR<0.05), most of which also showed a weaker transcriptional response in African-Americans. These results suggest that inter-ethnic differences in GC sensitivity reflect variation in transcriptional response at many genes, including regulators with large effects (e.g. NFKB1) and numerous other genes with smaller effects.

Evidence for the involvement of the glucocorticoid receptor gene in bipolar disorder in an isolated northern Swedish population

OBJECTIVES

Dysfunction of the hypothalamus-pituitary-adrenal (HPA) axis is one of the most consistent findings in the pathophysiology of mood disorders. The potential role of genes related to HPA axis function has been investigated extensively in major depression. However, in bipolar disorder (BPD) such studies are scarce. We performed a systematic HapMap-based association study of six genes crucial for HPA axis function in relation to BPD.

METHODS

Haplotype tagging single nucleotide polymorphisms (htSNPs) were selected in order to identify all haplotypes with a frequency of more than 1% in the genes encoding the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), corticotrophin releasing hormone receptor 1 (CRH-R1) and 2 (CRH-R2), CRH binding protein (CRH-BP), and FK binding protein 5 (FKBP5). This resulted in a total selection of 225 SNPs that were genotyped and analyzed in 309 BPD patients and 364 matched control individuals all originating from an isolated northern Swedish population.

RESULTS

Consistent evidence for an association with BPD was found for NR3C1, the gene encoding GR. Almost all SNPs in two adjacent haplotype blocks contributed to the positive signal, comprised of significant single marker, sliding window, and haplotype-specific p-values. All these results point to a moderately frequent (10-15%) susceptibility haplotype covering the entire coding region and 3' untranslated region (UTR) of NR3C1.

CONCLUSIONS

This study contributes to the growing evidence for a role of the glucocorticoid receptor gene (NR3C1) in vulnerability to mood disorders, and BPD in particular, and warrants further in vitro investigation of the at-risk haplotypes with respect to disease etiology. However, this association might be restricted to this specific population, as it is observed in a rather small sample from an isolated population without replication, and data from large meta-analyses for genome-wide association studies in BPD do not show the GR as a very strong candidate.

Interactions between glucocorticoid treatment and cis-regulatory polymorphisms contribute to cellular response phenotypes

Glucocorticoids (GCs) mediate physiological responses to environmental stress and are commonly used as pharmaceuticals. GCs act primarily through the GC receptor (GR, a transcription factor). Despite their clear biomedical importance, little is known about the genetic architecture of variation in GC response. Here we provide an initial assessment of variability in the cellular response to GC treatment by profiling gene expression and protein secretion in 114 EBV-transformed B lymphocytes of African and European ancestry. We found that genetic variation affects the response of nearby genes and exhibits distinctive patterns of genotype-treatment interactions, with genotypic effects evident in either only GC-treated or only control-treated conditions. Using a novel statistical framework, we identified interactions that influence the expression of 26 genes known to play central roles in GC-related pathways (e.g. NQO1, AIRE, and SGK1) and that influence the secretion of IL6.

Glucocorticoid receptor-9beta polymorphism is associated with systolic blood pressure and heart growth during early childhood. The Generation R Study

BACKGROUND

glucocorticoid receptor-9β polymorphism (rs6198) is associated with the susceptibility for cardiovascular disease.

AIM

to examine whether the GR-9 β variant is also associated with blood pressure and heart growth in early childhood.

STUDY DESIGN

this study was embedded in a population-based prospective cohort study from fetal life onwards. Analyses were based on 857 children.

OUTCOME MEASURES

Left cardiac structures (aortic root diameter, left atrial diameter and left ventricular mass), shortening fraction and heart beat were measured postnatally at the ages of 1.5, 6 and 24 months. Blood pressure was measured at 24 months of age.

RESULTS

the distribution of the GR-9β genotype showed 75.1% homozygous reference, 23.5% heterozygous and 1.4% homozygous variant subjects. No differences in cardiovascular outcomes were observed at the ages of 1.5 and 6 months. At the age of 24 months, homozygous variants showed an increased systolic blood pressure of 2.65 mmHg (95% CI: 0.16, 5.14), an increased heart rate of 9.10 beats per minute (95% CI: 1.28, 16.7) and an increased left ventricular mass of 4.99 g (95% CI: 1.33, 8.65) compared to homozygous references. This means an increase of 2.6%, 8.6% and 16%, respectively. GR-9 β polymorphism was significantly associated with left ventricular mass growth during the first 2 years.

CONCLUSION

our findings suggest that genetically determined differences in cortisol exposure affect cardiovascular development in early life.

Glucocorticoid receptor gene and depression in patients with coronary heart disease: the Heart and Soul Study-2009 Curt Richter Award Winner

Alterations of glucocorticoid receptor sensitivity have been associated with depression. Thus, variation in the glucocorticoid receptor gene that determines glucocorticoid sensitivity may influence risk for depression. In a cross-sectional genetic association study of 526 white outpatients with chronic coronary heart disease, we examined whether haplotypes of the glucocorticoid receptor gene (NR3C1) are associated with depression. Participants were genotyped for four common glucocorticoid receptor gene polymorphisms (ER22/23EK, BclI C/G, N363S, and 9beta A/G) and haplotype analyses were conducted. Depression was assessed by an interview (Computerized Diagnostic Interview Schedule). Of the 526 participants, 355 (67.5%) were non-carriers, 153 (29.1%) had one copy, and 17 (3.2%) had 2 copies of the haplotype 3 allele, which includes the minor allele of the 9beta A/G polymorphism and which has been associated with reduced glucocorticoid sensitivity. The prevalence of depression ranged from 24.4% in the non-carriers to 34.4% in heterozygotes to 52.9% in participants homozygous for the haplotype 3 allele (p<0.01). In logistic regression analyses, carriers of one haplotype 3 allele had an odds ratio of 1.64 (95% CI 1.1-2.5, p=0.02) for depression, while the odds ratio of homozygous haplotype 3 carriers was 3.52 (95% CI 1.3-9.4, p=0.01). These associations persisted after adjusting for potentially confounding variables. A common GR haplotype was associated with depression in a gene-dosage dependent manner and might be a vulnerability factor for depression.

Human glucocorticoid receptor alpha gene (NR3C1) pharmacogenomics: gene resequencing and functional genomics

CONTEXT

The human glucocorticoid receptor alpha (GRalpha) is a nuclear hormone receptor that regulates multiple physiological and pathophysiological processes. There are large variations in both physiological and therapeutic response to glucocorticoids. Multiple previous studies suggested that genetic polymorphisms in GRalpha (NR3C1) might play an important role.

OBJECTIVE

The aim of the study was to identify and determine the functional implications of common genetic variation in NR3C1.

DESIGN

We resequenced the NR3C1 gene using 240 DNA samples from four ethnic groups, followed by functional characterization of the effects of selected polymorphisms.

RESULTS

A total of 108 polymorphisms were identified in GRalpha, including nine nonsynonymous coding single nucleotide polymorphisms (cSNPs) and four synonymous cSNPs with a minor allele frequency greater than 5%. Functional studies showed that SNPs encoding Phe(65)Val and Asp(687)Glu displayed slightly increased levels of protein compared with WT, and Asp(687)Glu also caused increased GRalpha receptor number. In addition, Ala(229)Thr and Ile(292)Val showed slightly decreased ligand binding affinity in COS-1 cells. A genotype-phenotype association study of NR3C1 gene expression in 240 lymphoblastoid cell lines identified one SNP, Cm746T>C, located 5'-upstream of noncoding exon 1C, and one haplotype, Cm237delC/Cm238C>T/Cm240G>C in exon 1C of the gene that were associated with GRalpha mRNA expression and a trend with GRalpha number.

CONCLUSIONS

These results represent a step toward understanding the functional role of common sequence variation in the GRalpha gene (NR3C1) and the potential application of those SNPs in translational studies.