1Hum. Mol. Genet. 2011 Oct 20: 4076-81
TitleCommon variants at VRK2 and TCF4 conferring risk of schizophrenia.
AbstractCommon sequence variants have recently joined rare structural polymorphisms as genetic factors with strong evidence for association with schizophrenia. Here we extend our previous genome-wide association study and meta-analysis (totalling 7 946 cases and 19 036 controls) by examining an expanded set of variants using an enlarged follow-up sample (up to 10 260 cases and 23 500 controls). In addition to previously reported alleles in the major histocompatibility complex region, near neurogranin (NRGN) and in an intron of transcription factor 4 (TCF4), we find two novel variants showing genome-wide significant association: rs2312147[C], upstream of vaccinia-related kinase 2 (VRK2) [odds ratio (OR) = 1.09, P = 1.9 10(-9)] and rs4309482[A], between coiled-coiled domain containing 68 (CCDC68) and TCF4, about 400 kb from the previously described risk allele, but not accounted for by its association (OR = 1.09, P = 7.8 10(-9)).
SCZ Keywordsschizophrenia
2Biol. Psychiatry 2012 Oct 72: 620-8
TitleGenome-wide association study implicates HLA-C*01:02 as a risk factor at the major histocompatibility complex locus in schizophrenia.
AbstractWe performed a genome-wide association study (GWAS) to identify common risk variants for schizophrenia.
The discovery scan included 1606 patients and 1794 controls from Ireland, using 6,212,339 directly genotyped or imputed single nucleotide polymorphisms (SNPs). A subset of this sample (270 cases and 860 controls) was subsequently included in the Psychiatric GWAS Consortium-schizophrenia GWAS meta-analysis.
One hundred eight SNPs were taken forward for replication in an independent sample of 13,195 cases and 31,021 control subjects. The most significant associations in discovery, corrected for genomic inflation, were (rs204999, p combined = 1.34 10(-9) and in combined samples (rs2523722 p combined = 2.88 10(-16)) mapped to the major histocompatibility complex (MHC) region. We imputed classical human leukocyte antigen (HLA) alleles at the locus; the most significant finding was with HLA-C*01:02. This association was distinct from the top SNP signal. The HLA alleles DRB1*03:01 and B*08:01 were protective, replicating a previous study.
This study provides further support for involvement of MHC class I molecules in schizophrenia. We found evidence of association with previously reported risk alleles at the TCF4, VRK2, and ZNF804A loci.
SCZ Keywordsschizophrenia
3Schizophr. Res. 2012 Dec 142: 200-5
TitleMeta-analysis and brain imaging data support the involvement of VRK2 (rs2312147) in schizophrenia susceptibility.
AbstractRecent genome-wide association studies have reported a set of schizophrenia susceptibility genes, but many of them await further replications in additional samples. Here we analyzed 5 genome-wide supported variants in a Han Chinese sample, and the variant rs2312147 at VRK2 showed significant association, which was confirmed in the meta-analysis combining multiple Asian and European samples (P=3.1710(-4), N=7498). Rs2312147 is also associated with brain structure in healthy subjects, including the total brain volume and the white matter volume. Gene expression analyses indicated an up-regulation of VRK2 in schizophrenia patients. Our data provide further evidence for the contribution of VRK2 to schizophrenia.
SCZ Keywordsschizophrenia
4PLoS ONE 2014 -1 9: e103519
TitleEffects of VRK2 (rs2312147) on white matter connectivity in patients with schizophrenia.
AbstractRecent genome-wide association studies of schizophrenia reported a novel risk variant, rs2312147 at vaccinia-related kinase 2 gene (VRK2), in multiple Asian and European samples. However, its effect on the brain structure in schizophrenia is little known. We analyzed the brain structure of 36 schizophrenia patients and 18 healthy subjects with regard to rs2312147 genotype groups. Brain magnetic resonance scans for gray matter (GM) and white matter (WM) analysis, and genotype analysis for VRK2 rs2312147, were conducted. The Positive and Negative Syndrome Scale and the Digit Symbol Test were assessed for schizophrenia patients. There was no significant difference in either GM volume or WM connectivity with regard to rs2312147 genotype in healthy subjects. In contrast, we found significant differences in the WM connectivity between rs2312147 CC and CT/TT genotype groups of schizophrenia patients. The related brain areas included the splenium of corpus callosum, the left occipital lobe WM, the internal capsule (left anterior limb and right retrolenticular part), the bilateral temporal lobe WM, the left fornix/stria terminalis, the left cingulate gyrus WM, and the left parietal lobe WM. Voxelwise correlation analysis revealed that the Digit Symbol Test scores (age corrected) correlated with the fractional anisotropy in WM tracts that previously showed significant group differences between the CT/TT and CC genotypes in the rs2312147 CT/TT genotype group, while no significant correlation was found in the CC genotype group. Our data may provide evidence for the effect of VRK2 on WM connectivity in patients with schizophrenia.
SCZ Keywordsschizophrenia
5Genetika 2015 Feb 51: 227-35
Title[Replicative study of susceptibility to childhood-onset schizophrenia in Kazakhs].
AbstractThis paper reports the results of replicative analysis of associations of 15 SNPs in a region of 14 genes previously identified in genome-wide association studies (GWAS) with early-onset schizophrenia in Kazakhs. An association of early-onset schizophrenia with genetic markers in three genes (VRK2, KCNB2, and CPVL) was found. An association of rs2312147 in the VRK2 gene with schizophrenia was also previously reported in the Chinese population, so this marker may be considered as possibly race-specific. Two groups consisting of four and six genes demonstrating intergenic epistatic interactions were revealed by multifactor dimensionality reduction methods. The gene ontologies of 14 studied genes were reduced to variants of one molecular function (peptidase activity) and one biological process (positive regulation of biosynthesis processes). Bioinformatic analysis of the protein-protein interactions of products of the genes under study demonstrates that the products of six out of 14 genes may be involved in a single interrelated network, the major connecting link of which is represented by their ubiquitination by the UBC protein.
SCZ Keywordsschizophrenia
6Genet. Mol. Res. 2015 -1 14: 9404-11
TitleAssociation of the VRK2 gene rs3732136 polymorphism with schizophrenia in a Northwest Chinese Han population.
AbstractPrevious studies have found that the vaccinia related kinase 2 gene (VRK2) polymorphism was associated with schizophrenia (SCZ) in the worldwide population. This association was further supported by VRK2 mRNA expression patterns and brain structure variations. Here, we analyzed four single nucleotide polymorphisms (SNPs) of the VRK2 gene in a total population of 893 samples, consisting of 360 patients with SCZ and 533 healthy controls of Han Chinese descent using the SNPscan method. Single SNP, haplotype, and gender-specific association analyses were performed. We found that rs3732136 was significantly associated with SCZ (P = 0.042; odds ratio = 1.25; 95% confidence interval = 1.01-1.55). Further genotype and haplotype association analyses suggested a similar pattern. Our data provide preliminary evidence that the VRK2 gene might play a major role in the development of SCZ in the Northwest Chinese Han population.
SCZ Keywordsschizophrenia
7Br J Psychiatry 2016 Mar -1: -1
TitleVRK2 gene expression in schizophrenia, bipolar disorder and healthy controls.
AbstractCommon variants in the Vaccinia-related kinase 2 (VRK2) gene have been associated with schizophrenia, but the relevance of its encoded protein VRK2 in the disorder remains unclear.
To identify potential differences in VRK2 gene expression levels between schizophrenia, bipolar disorder, psychosis not otherwise specified (PNOS) and healthy controls.
VRK2 mRNA level was measured in whole blood in 652 individuals (schizophrenia, n = 201; bipolar disorder, n = 167; PNOS, n = 61; healthy controls, n = 223), and compared across diagnostic categories and subcategories. Additionally, we analysed for association between 1566 VRK2 single nucleotide polymorphisms and mRNA levels.
We found lower VRK2 mRNA levels in schizophrenia compared with healthy controls (P<10(-12)), bipolar disorder (P<10(-12)) and PNOS (P = 0.0011), and lower levels in PNOS than in healthy controls (P = 0.0042) and bipolar disorder (P = 0.00026). Expression quantitative trait loci in close proximity to the transcription start site of the short isoforms of the VRK2 gene were identified.
Altered VRK2 gene expression seems specific for schizophrenia and PNOS, which is in accordance with findings from genome-wide association studies. These results suggest that reduced VRK2 mRNA levels are involved in the underlying mechanisms in schizophrenia spectrum disorders.
SCZ Keywordsschizophrenia