Genetic analysis of common variants in the CMYA5 (cardiomyopathy-associated 5) gene with schizophrenia

Association Analysis of CMYA5 rs4704591 Polymorphism with Rheumatoid Arthritis in Caucasians

Einleitung Einzel nukleotid polymorphismen (SNPs) im Cardiomyopathy-Associated Protein 5 (CMYA5)-Gen wurden in genomweiten Assoziationsstudien mit rheumatoider Arthritis (RA) in Verbindung gebracht. In dieser Studie wollten wir die Assoziation zwischen CMYA5-Genpolymorphismen und RA in unabhängigen kaukasischen Fall-Kontroll-Kohorten replizieren und eine Metaanalyse durchführen, um die Assoziation von CMYA5-Genpolymorphismen mit RA in kaukasischen Populationen zu untersuchen.

Methoden Wir analysierten 2731 RA-Fälle und 1783 gesunde Kontrollen in vier unabhängigen kaukasischen Probensätzen. rs4704591 im CMYA5-Gen wurden unter Verwendung des TaqMan SNP-Genotypisierungsassays genotypisiert. Die Metaanalyse wurde über kaukasische Kohorten hinweg durchgeführt.

Ergebnisse Unsere Analyse ergab keine Hinweise auf eine Assoziation von rs4704591 mit RA in den Replikationsprobensätzen (P=0,941, OR=0,997). Die Metaanalyse zeigte eine schwache Assoziation zwischen dem kleinen Allel der CMYA5-Variante rs4704591 (C) und RA in den kombinierten RA-Kohorten (P=0,023, OR=0,938) unter Verwendung des logistischen Regressionsmodells in der Matched-Case-Control-Studie.

Schlussfolgerung Unsere Studie war nicht erfolgreich darin, die Assoziation der CMYA5-Variante rs4704591 mit RA zu replizieren. Daher können wir die Assoziation zwischen CMYA5-Genpolymorphismen und RA in der kaukasischen Bevölkerung nicht bestätigen.

CMYA5 is a novel interaction partner of FHL2 in cardiac myocytes

Four-and-a-half LIM domains protein 2 (FHL2) is an anti-hypertrophic adaptor protein that regulates cardiac myocyte signalling and function. Herein, we identified cardiomyopathy-associated 5 (CMYA5) as a novel FHL2 interaction partner in cardiac myocytes. In vitro pull-down assays demonstrated interaction between FHL2 and the N- and C-terminal regions of CMYA5. The interaction was verified in adult cardiac myocytes by proximity ligation assays. Immunofluorescence and confocal microscopy demonstrated co-localisation in the same subcellular compartment. The binding interface between FHL2 and CMYA5 was mapped by peptide arrays. Exposure of neonatal rat ventricular myocytes to a CMYA5 peptide covering one of the FHL2 interaction sites led to an increase in cell area at baseline, but a blunted response to chronic phenylephrine treatment. In contrast to wild-type hearts, loss or reduced FHL2 expression in Fhl2-targeted knockout mouse hearts or in a humanised mouse model of hypertrophic cardiomyopathy led to redistribution of CMYA5 into the perinuclear and intercalated disc region. Taken together, our results indicate a direct interaction of the two adaptor proteins FHL2 and CMYA5 in cardiac myocytes, which might impact subcellular compartmentation of CMYA5.

Rare Pathogenic Variants in Genes Implicated in Glutamatergic Neurotransmission Pathway Segregate with Schizophrenia in Pakistani Families

Schizophrenia is a disabling neuropsychiatric disorder of adulthood onset with high heritability. Worldwide collaborations have identified an association of ~270 common loci, with small individual effects and hence weak clinical implications. The recent technological feasibility of exome sequencing enables the identification of rare variants of high penetrance that refine previous findings and improve risk assessment and prognosis. We recruited two multiplex Pakistani families, having 11 patients and 19 unaffected individuals in three generations. We performed genome-wide SNP genotyping, next-generation mate pairing and whole-exome sequencing of selected members to unveil genetic components. Candidate variants were screened in unrelated cohorts of 508 cases, 300 controls and fifteen families (with 51 affected and 47 unaffected individuals) of Pakistani origin. The structural impact of substituted residues was assessed through in silico modeling using iTASSER. In one family, we identified a rare novel microduplication (5q14.1_q14.2) encompassing critical genes involved in glutamate signaling, such as CMYA5, HOMER and RasGRF2. The second family segregates two ultra-rare, predicted pathogenic variants in the GRIN2A (NM_001134407.3: c.3505C>T, (p.R1169W) and in the NRG3 NM_001010848.4: c.1951G>A, (p.E651K). These genes encode for parts of AMPA and NMDA receptors of glutamatergic neurotransmission, respectively, and the variants are predicted to compromise protein function by destabilizing their structures. The variants were absent in the aforementioned cohorts. Our findings suggest that rare, highly penetrant variants of genes involved in glutamatergic neurotransmission are contributing to the etiology of schizophrenia in these families. It also highlights that genetic investigations of multiplex, multigenerational families could be a powerful approach to identify rare genetic variants involved in complex disorders.

Myospryn deficiency leads to impaired cardiac structure and function and schizophrenia-associated symptoms

The desmin-associated protein myospryn, encoded by the cardiomyopathy-associated gene 5 (CMYA5), is a TRIM-like protein associated to the BLOC-1 (Biogenesis of Lysosomes Related Organelles Complex 1) protein dysbindin. Human myospryn mutations are linked to both cardiomyopathy and schizophrenia; however, there is no evidence of a direct causative link of myospryn to these diseases. Therefore, we sought to unveil the role of myospryn in heart and brain. We have genetically inactivated the myospryn gene by homologous recombination and demonstrated that myospryn null hearts have dilated phenotype and compromised cardiac function. Ultrastructural analyses revealed that the sarcomere organization is not obviously affected; however, intercalated disk (ID) integrity is impaired, along with mislocalization of ID and sarcoplasmic reticulum (SR) protein components. Importantly, cardiac and skeletal muscles of myospryn null mice have severe mitochondrial defects with abnormal internal vacuoles and extensive cristolysis. In addition, swollen SR and T-tubules often accompany the mitochondrial defects, strongly implying a potential link of myospryn together with desmin to SR- mitochondrial physical and functional cross-talk. Furthermore, given the reported link of human myospryn mutations to schizophrenia, we performed behavioral studies, which demonstrated that myospryn-deficient male mice display disrupted startle reactivity and prepulse inhibition, asocial behavior, decreased exploratory behavior, and anhedonia. Brain neurochemical and ultrastructural analyses revealed prefrontal-striatal monoaminergic neurotransmitter defects and ultrastructural degenerative aberrations in cerebellar cytoarchitecture, respectively, in myospryn-deficient mice. In conclusion, myospryn is essential for both cardiac and brain structure and function and its deficiency leads to cardiomyopathy and schizophrenia-associated symptoms.

Emerging Role of TRIM Family Proteins in Cardiovascular Disease

Ubiquitination is one of the basic mechanisms of cell protein homeostasis and degradation and is accomplished by 3 enzymes, E1, E2, and E3. Tripartite motif-containing proteins (TRIMs) constitute the largest subfamily of RING E3 ligases, with >70 current members in humans and mice. These members are involved in multiple biological processes, including growth, differentiation, and apoptosis as well as disease and tumorigenesis. Accumulating evidence has shown that many TRIM proteins are associated with various cardiac processes and pathologies, such as heart development, signal transduction, protein degradation, autophagy mediation, ion channel regulation, congenital heart disease, and cardiomyopathies. In this review, we provide an overview of the TRIM family and discuss its involvement in the regulation of cardiac proteostasis and pathophysiology and its potential therapeutic implications.

Further evidence for the association between LRP8 and schizophrenia

Previous studies (including genome-wide association study (GWAS) and candidate gene studies) have revealed the important roles of genetic risk factors in schizophrenia, and RELN has been identified as a risk gene for this illness. We recently found that the low-density lipoprotein receptor-related protein 8 (LRP8), a receptor of Reelin (the protein encoded by RELN), was significantly associated with schizophrenia and bipolar disorder in European populations. To further enhance our understanding of its role in the risk of psychiatric illnesses, we conducted meta-analyses of a higher density of single nucleotide polymorphisms (SNPs, N=173) in LRP8 to understand their associations with schizophrenia in much larger samples (39,400 cases and 50,357 controls) from populations of European, Chinese and African American ancestries. The significant risk SNPs then underwent further analyses to understand their correlations with bipolar disorder and anxiety disorders, as well as LRP8 expression. We observed that rs5177 in the 3' untranslated region (3'UTR) of LRP8 was associated with schizophrenia and other psychiatric disorders, and rs5177 was also associated with LRP8 mRNA expression. These data further support LRP8 as a schizophrenia susceptibility gene, and suggest that this variant is likely a risk locus in general populations.

A schizophrenia associated CMYA5 allele displays differential binding with desmin

CMYA5 is a candidate gene for schizophrenia because of the genetic association of variant rs10043986 (C > T) to this severe mental disorder. Studies of CMYA5 and its gene product, myospryn, in the brain and neuronal cells have not been previously reported. The SNP rs10043986 changes the 4,063rd amino acid from Pro to Leu, which is likely to alter protein function. To understand its potential role in the brain, we examined the neuronal expression of myospryn and its binding partner, desmin, an intermediate filament (IF) protein, and investigated how the two alleles of myospryn affect its binding to desmin. Myospryn and desmin are shown to be expressed in the brain and myospryn is shown to localize to the cytoplasm and nucleus of myoblast, neuroblastoma, and glioblastoma cell lines. Peripherin and vimentin, known brain IF proteins, have high protein similarity to desmin but were found not to interact with myospryn using yeast two-hybrid (Y2H). Using a quantitative Y2H assay and surface plasmon resonance, the T allele (Leu) of rs10043986 was found to have stronger binding to desmin than the C allele (Pro). Based on findings described in this report, we hypothesize that the interaction between myospryn to IF provides structural support and efficient rearrangement of the cytoskeleton network during early neuritogenesis.

Updated meta-analysis of CMYA5 rs3828611 and rs4704591 with schizophrenia in Asian populations

AIM

Two single-nucleotide polymorphisms, rs3828611 and rs4704591, in the cardiomyopathy-associated protein 5 (CMYA5) gene have been extensively investigated for associations with schizophrenia in Asian populations, but with conflicting results. To assess the collective evidence across individual studies, we conducted an updated meta-analysis.

METHODS

We performed a random-effect model meta-analysis of the associations of rs3828611 and rs4704591 with schizophrenia using seven case-control samples from Asian populations (8074 patients and 8139 controls).

RESULTS

The meta-analysis indicated that rs3828611 and rs4704591 were not significantly associated with schizophrenia (odds ratios [OR] = 0.93, 95% confidence interval [CI] = 0.85-1.01 and OR = 0.99, 95% CI = 0.93-1.05, respectively).

CONCLUSIONS

Our meta-analysis did not provide evidence supporting a contribution of CMYA5 rs3828611 and rs4704591 to schizophrenia susceptibility in Asian populations.

The cAMP responsive element-binding (CREB)-1 gene increases risk of major psychiatric disorders

Bipolar disorder (BPD), schizophrenia (SCZ) and unipolar major depressive disorder (MDD) are primary psychiatric disorders sharing substantial genetic risk factors. We previously reported that two single-nucleotide polymorphisms (SNPs) rs2709370 and rs6785 in the cAMP responsive element-binding (CREB)-1 gene (CREB1) were associated with the risk of BPD and abnormal hippocampal function in populations of European ancestry. In the present study, we further expanded our analyses of rs2709370 and rs6785 in multiple BPD, SCZ and MDD data sets, including the published Psychiatric Genomics Consortium (PGC) genome-wide association study, the samples used in our previous CREB1 study, and six additional cohorts (three new BPD samples, two new SCZ samples and one new MDD sample). Although the associations of both CREB1 SNPs with each illness were not replicated in the new cohorts (BPD analysis in 871 cases and 1089 controls (rs2709370, P=0.0611; rs6785, P=0.0544); SCZ analysis in 1273 cases and 1072 controls (rs2709370, P=0.230; rs6785, P=0.661); and MDD analysis in 129 cases and 100 controls (rs2709370, P=0.114; rs6785, P=0.188)), an overall meta-analysis of all included samples suggested that both SNPs were significantly associated with increased risk of BPD (11 105 cases and 51 331 controls; rs2709370, P=2.33 × 10^-4; rs6785, P=6.33 × 10^-5), SCZ (34 913 cases and 44 528 controls; rs2709370, P=3.96 × 10^-5; rs6785, P=2.44 × 10^-5) and MDD (9369 cases and 9619 controls; rs2709370, P=0.0144; rs6785, P=0.0314), with the same direction of allelic effects across diagnostic categories. We then examined the impact of diagnostic status on CREB1 mRNA expression using data obtained from independent brain tissue samples, and observed that the mRNA expression of CREB1 was significantly downregulated in psychiatric patients compared with healthy controls. The protein-protein interaction analyses showed that the protein encoded by CREB1 directly interacted with several risk genes of psychiatric disorders identified by GWAS. In conclusion, the current study suggests that CREB1 might be a common risk gene for major psychiatric disorders, and further investigations are necessary.

Association between CMYA5 gene polymorphisms and risk of schizophrenia in Uygur population and a meta-analysis

AIM

Previous evidence has found that some single nucleotide polymorphisms (SNPs) in cardiomyopathy-associated 5 gene (CMYA5) were associated with schizophrenia in the Caucasian and Chinese Han populations. In this study, we aimed to investigate the relationship between CMYA5 gene polymorphisms and schizophrenia in Chinese Uygur population and perform a meta-analysis to synthetically analyse the association of CMYA5 gene polymorphisms with schizophrenia in Asian populations.

METHOD

We retrospectively analysed 985 schizophrenia cases and 1123 healthy controls in Chinese Uygur population. Four SNPs (rs259127, rs3828611, rs4704591 and rs6883197) of CMYA5 were genotyped using TaqMan SNP genotyping assay. Meta-analysis was conducted across Asian studies by Review Manager 5.2.

RESULTS

Results showed no significant difference in either allelic or genotypic frequency in four SNPs of the CMYA5 gene between cases and controls (P > 0.05). However, the age of onset and the PANSS positive-factor subscale score were significantly lower in schizophrenia patients with the A/A genotype of rs6883197 than those with A/G and G/G genotypes (P < 0.05). In addition, the meta-analysis showed the significant association of rs3828611 with risk of schizophrenia (P = 0.03, OR = 0.92, 95% CI: 0.91-0.99).

CONCLUSIONS

Our results support the association between CMYA5 rs6883197 and schizophrenia in Chinese Uygur population. Meta-analysis demonstrated that rs3828611 was significantly associated with schizophrenia in Asian population. Genetic heterogeneity among populations may be the main reason of results conflict between studies. In conclusion, association between CMYA5 gene polymorphisms and schizophrenia was confirmed in Asian population.

The CMYA5 gene confers risk for both schizophrenia and major depressive disorder in the Han Chinese population

OBJECTIVES

A recent genome-wide association study (GWAS) of the European population implicated the CMYA5 gene in schizophrenia. Previous functional studies showed that the CMYA5 protein can interact with DTNBP1 and PKA, providing further support for a role of CMYA5 in the pathogenesis of schizophrenia. However, this association requires additional validation in independent populations.

METHODS

To validate the association between CMYA5 and schizophrenia and major depressive disorder, we genotyped 16 SNPs within the CMYA5 gene and performed case-control studies in 1330 schizophrenia patients, 1045 patients with major depressive disorder, and 1235 normal controls. All patients were of Han Chinese origin.

RESULTS

rs6883197 and rs259127 were significantly associated with schizophrenia, and rs12514461, rs259127, and rs7343 were associated with major depressive disorder. Additionally, one risk haplotype of rs16877109-rs3828611 (G-G) was associated with both schizophrenia (P = 0.0000784, after correction) and major depressive disorder (P = 0.00230, after correction).

CONCLUSIONS

Our findings support the idea that specific alleles and haplotype in the CMYA5 confer genetic risk for both schizophrenia and major depressive disorder in the Han Chinese population.