Association between RGS4 variants and psychotic-like experiences in nonclinical individuals

Moderating and mediating effects of resilience between childhood trauma and psychotic-like experiences among college students

BACKGROUND

Extensive literature revealed that childhood trauma serves as a significant risk factor for developing psychotic-like experiences (PLEs) among the general population. Resilience has been regarded as a protective factor against PLEs. However, it remains unclear what role resilience plays in the relationship between childhood trauma and PLEs.

METHODS

A total of 4302 college students completed the web-based survey in January 2021. Participants completed self-report measures of sample characteristics variables, childhood trauma, and PLEs. Moderation and mediation analyses were adopted to examine the associations linking childhood trauma, resilience, and PLEs.

RESULTS

PLEs were positively associated with childhood trauma while negatively associated with resilience. Resilience played a partially mediating role in the relationship between childhood trauma and PLEs. Additionally, resilience moderated the association of childhood trauma with PLEs.

CONCLUSIONS

These findings indicated that resilience plays a crucial role in mediating the relationship between childhood trauma and PLEs, suggesting the potential clinical implication of enhancing resilience for the prevention and intervention of PLEs among college students.

Schizophrenia polygenic risk score in psychosis proneness

Schizophrenia (SZ) is a complex disorder with a highly polygenic inheritance. It can be conceived as the extreme expression of a continuum of traits that are present in the general population often broadly referred to as schizotypy. However, it is still poorly understood how these traits overlap genetically with the disorder. We investigated whether polygenic risk for SZ is associated with these disorder-related phenotypes (schizotypy, psychotic-like experiences, and subclinical psychopathology) in a sample of 253 non-clinically identified participants. Polygenic risk scores (PRSs) were constructed based on the latest SZ genome-wide association study using the PRS-CS method. Their association with self-report and interview measures of SZ-related traits was tested. No association with either schizotypy or psychotic-like experiences was found. However, we identified a significant association with the Motor Change subscale of the Comprehensive Assessment of At-Risk Mental States (CAARMS) interview. Our results indicate that the genetic overlap of SZ with schizotypy and psychotic-like experiences is less robust than previously hypothesized. The relationship between high PRS for SZ and motor abnormalities could reflect neurodevelopmental processes associated with psychosis proneness and SZ.

A gene-based review of RGS4 as a putative risk gene for psychiatric illness

Considerable efforts have been made to characterize RGS4 as a potential candidate gene for schizophrenia. Investigations span across numerous modalities and include explorations of genetic risk associations, mRNA and protein levels in the brain, and functionally relevant interactions with other candidate genes as well as links to schizophrenia relevant neural phenotypes. While these lines of investigations have yielded partially inconsistent findings, they provide a perspective on RGS4 as an important part of a larger biological system contributing to schizophrenia risk. This gene-based review aims to provide a comprehensive overview of published data from different experimental modalities and discusses the current knowledge of RGS4's systems-biological impact on the schizophrenia pathology.

Analysis of the association of MIR124-1 and its target gene RGS4 polymorphisms with major depressive disorder and antidepressant response

BACKGROUND

Increasing evidence has indicated that dysfunction of miR-124 and target gene regulator of G protein signaling 4 (RGS4) may be involved in the etiology and treatment of major depressive disorder (MDD). However, the molecular mechanisms are not fully understood. This study aimed to investigate whether common genetic variations in these two genes are associated with MDD and therapeutic response to antidepressants in the Chinese population.

METHODS

Three polymorphisms including rs531564 (a functional single-nucleotide polymorphism [SNP] in MIR124-1), rs10759 (a microRNA-binding site SNP in RGS4), and rs951436 (a promoter SNP in RGS4) were genotyped in 225 Chinese MDD patients and 436 controls. Among the MDD patients, 147 accepted antidepressant treatment for 8 weeks with therapeutic evaluation at baseline, week 2, week 4, week 6, and week 8 using the 17-item Hamilton Rating Scale for Depression. Multifactor dimensionality reduction (MDR) was used to identify gene-gene interactions.

RESULTS

No significant association with MDD was discovered in single-SNP analyses. However, by MDR analysis, the three-locus model of gene-gene interaction was the best for predicting MDD risk. In pharmacogenetic study, a significant association was found in genotypic frequencies of rs951436 between the remitter and non-remitter groups (p=0.026, correction p=0.078). For further analysis, the rs951436 heterozygote carriers had threefold probabilities of achieving clinical complete remission (odds ratio =3.00, 95% confidence interval =1.33-6.76, p=0.007, correction p=0.021) as compared with rs951436 homozygotes (AA+CC) after 8 weeks of treatment.

CONCLUSION

An interaction effect of MIR124-1 and RGS4 polymorphisms may play a more important role than individual factors for MDD development. Moreover, RGS4 gene polymorphisms may be associated with antidepressant response among the Han population.

Interaction between FKBP5 gene and childhood trauma on psychosis, depression and anxiety symptoms in a non-clinical sample

BACKGROUND

Childhood trauma has been associated with a heightened risk for presenting clinical and non-clinical psychopathology in adulthood. Genes related with the stress response, such as the FK506 binding protein 51 (FKBP5), are plausible candidates moderating the effects of childhood trauma on the emergence of such symptoms later on. The present study aimed to explore the moderating role of FKBP5 genetic variability on the association of different types of childhood trauma with subclinical psychosis, depression and anxiety in a non-clinical sample.

METHODS

Schizotypy, psychotic-like experiences, depression and anxiety symptoms and childhood trauma were assessed in 808 young adults. Two FKBP5 haplotypic blocks were detected: block 1 (rs3800373 - rs9296158 - rs1360780) and block 2 (rs9470080 - rs4713916). Subjects were classified in two groups according to whether they carried or not the risk haplotype previously described in the literature (block 1: CAT and block 2: TA). Linear regression analyses were used to study (i) the main effects of childhood trauma and FKBP5 haplotype blocks and (ii) their interaction effects on the mentioned forms of psychopathology.

RESULTS

All childhood trauma scales, except sexual abuse, were associated with schizotypy, psychotic-like experiences, depression and anxiety symptoms. None of the analysed symptoms was associated with the main effects of FKBP5 genetic variability. However an interaction effect between block 1 and physical abuse was observed on anxiety, with lower scores in CAT carriers. This effect was driven by SNP 1 and 2. Moreover, an interaction effect between block 2 and physical abuse was identified on the variables tapping depressive and anxiety symptoms. Specifically, non-TA carrier subjects who were exposed to physical abuse were found to be at higher risk for depressive and anxiety symptoms. These effects were driven by SNP 5. No interaction effect was observed for the other variables.

CONCLUSIONS

Our data suggest that exposure to childhood physical abuse may increase the risk for sub-clinical depressive and anxiety symptoms depending on FKBP5 genetic variability. Further research is needed to better elucidate the role of FKBP5 on mental health in clinical and non-clinical cohorts.

The role of stress-regulation genes in moderating the association of stress and daily-life psychotic experiences

OBJECTIVE

The interaction of single nucleotide polymorphisms with both distal and proximal environmental factors across the extended psychosis phenotype is understudied. This study examined (i) the interaction of relevant SNPs with both early-life adversity and proximal (momentary) stress on psychotic experiences (PEs) in an extended psychosis sample; and (ii) differences between early-psychosis and non-clinical groups for these interactions.

METHODS

Two hundred and forty-two non-clinical and 96 early-psychosis participants were prompted randomly eight times daily for 1 week to complete assessments of current experiences, including PEs and stress. Participants also reported on childhood trauma and were genotyped for 10 SNPs on COMT, RGS4, BDNF, FKBP5, and OXTR genes.

RESULTS

Unlike genetic variants, distal and proximal stressors were associated with PEs in both samples and were more strongly associated with PEs in the early-psychosis than in the non-clinical group. The RGS4 TA and FKBP5 CATT haplotypes interacted with distal stress, whereas the A allele of OXTR (rs2254298) interacted with proximal stress, increasing momentary levels of PEs in the early-psychosis group. No interactions emerged with COMT or BDNF variants.

CONCLUSION

Individual differences in relevant stress-regulation systems interact with both distal and proximal psychosocial stressors in shaping the daily-life manifestation of PEs across the psychosis continuum.

Childhood trauma, BDNF Val66Met and subclinical psychotic experiences. Attempt at replication in two independent samples

Childhood trauma exposure is a robust environmental risk factor for psychosis. However, not all exposed individuals develop psychotic symptoms later in life. The Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism (rs6265) has been suggested to moderate the psychosis-inducing effects of childhood trauma in clinical and nonclinical samples. Our study aimed to explore the interaction effect between childhood trauma and the BDNF Val66Met polymorphism on subclinical psychotic experiences (PEs). This was explored in two nonclinical independent samples: an undergraduate and technical-training school student sample (n = 808, sample 1) and a female twin sample (n = 621, sample 2). Results showed that childhood trauma was strongly associated with positive and negative PEs in nonclinical individuals. A BDNF Val66Met x childhood trauma effect on positive PEs was observed in both samples. These results were discordant in terms of risk allele: while in sample 1 Val allele carriers, especially males, were more vulnerable to the effects of childhood trauma regarding PEs, in sample 2 Met carriers presented higher PEs scores when exposed to childhood trauma, compared with Val carriers. Moreover, in sample 2, a significant interaction was also found in relation to negative PEs. Our study partially replicates previous findings and suggests that some individuals are more prone to develop PEs following childhood trauma because of a complex combination of multiple factors. Further studies including genetic, environmental and epigenetic factors may provide insights in this field.