Identification of rare nonsynonymous variants in SYNE1/CPG2 in bipolar affective disorder.

Background: Bipolar affective disorder (BPD) is a severe mood disorder with a prevalence of ∼1.5% in the population. The pathogenesis of BPD is poorly understood; however, a strong heritable component has been identified.

Analysis of ANK3 and CACNA1C variants identified in bipolar disorder whole genome sequence data.

Objectives: Genetic markers in the genes encoding ankyrin 3 (ANK3) and the α-calcium channel subunit (CACNA1C) are associated with bipolar disorder (BP). The associated variants in the CACNA1C gene are mainly within intron 3 of the gene. ANK3 BP-associated variants are in two distinct clusters at the ends of the gene, indicating disease allele heterogeneity.

Genetic association, mutation screening, and functional analysis of a Kozak sequence variant in the metabotropic glutamate receptor 3 gene in bipolar disorder.

Importance: Genetic markers at the gene encoding the metabotropic glutamate receptor 3 (GRM3) showed allelic association with bipolar disorder.

Objective: To screen the GRM3 gene and adjacent control regions of genomic DNA in volunteers with bipolar affective disorder for mutations increasing susceptibility to bipolar disorder.

Design: Sequencing and high-resolution melting curve analysis of DNA followed by genotyping was carried out in 1099 patients with bipolar affective disorder and 1152 healthy comparator individuals.

Sequencing of the ANKYRIN 3 gene (ANK3) encoding ankyrin G in bipolar disorder reveals a non-conservative amino acid change in a short isoform of ankyrin G.

Significant association between polymorphisms at the ANK3 gene with bipolar disorder has previously been reported and confirmed in several samples. Here we report on association between ANK3 and bipolar disorder in a new sample of 593 patients and 642 controls (UCL2) as well as the results of sequencing of the exons and flanking regions of ANK3 from bipolar patients. Single nucleotide polymorphisms (SNPs) associated with bipolar disorder in our original GWA study (UCL1) were genotyped and tested for association in the new sample.

Confirmation of prior evidence of genetic susceptibility to alcoholism in a genome-wide association study of comorbid alcoholism and bipolar disorder.

Objectives: Alcoholism and affective disorders are both strongly comorbid and heritable. We have investigated the genetic comorbidity between bipolar affective disorder and alcoholism.

Methods: A genome-wide allelic association study of 506 patients from the University College London bipolar disorder case-control sample and 510 ancestrally matched supernormal controls.

Genetic association and sequencing of the insulin-like growth factor 1 gene in bipolar affective disorder.

Insulin-like growth factor 1 (IGF1) has been shown to have an important role in brain development and function. Studies of IGF1 administration in rodents have shown that it has an anxiolytic and antidepressant effect. A genome-wide association study (GWAS) of the first University College London (UCL) cohort of 506 bipolar affective disorder subjects and 510 controls was carried out.

Analysis of genetic deletions and duplications in the University College London bipolar disorder case control sample.

Genetic deletions and duplications known as copy number variants have been strongly implicated in genetic susceptibility to schizophrenia, autism, attention deficit hyperactivity disorder and epilepsy. The overall rate of copy number variants in the University College London (UCL) bipolar disorder sample was found to be slightly lower than the rate in controls. This finding confirms the results from other studies that have also shown no increased rate of copy number variants in bipolar disorder.

Case-case genome-wide association analysis shows markers differentially associated with schizophrenia and bipolar disorder and implicates calcium channel genes.

Objective: There are theoretical reasons why comparing marker allele frequencies between cases of different diseases, rather than with controls, may offer benefits. The samples may be better matched, especially for background risk factors common to both diseases. Genetic loci may also be detected which influence which of the two diseases occurs if common risk factors are present.

No evidence for excess runs of homozygosity in bipolar disorder.

Background: Recent studies have reported large common regions of homozygosity (ROHs) that are the result of autozygosity, that is, the cooccurrence within individuals of long haplotypes that have a high frequency in the population. A recent study reports that such regions are found more commonly in individuals with schizophrenia compared with controls, and identified nine 'risk ROHs' that were individually more common in cases. Of these, four contained or neighboured genes associated with schizophrenia (NOS1AP/UHMK1, ATF2, NSF and PIK3C3).

Collaborative genome-wide association analysis supports a role for ANK3 and CACNA1C in bipolar disorder.

To identify susceptibility loci for bipolar disorder, we tested 1.8 million variants in 4,387 cases and 6,209 controls and identified a region of strong association (rs10994336, P = 9.1 x 10(-9)) in ANK3 (ankyrin G).