Electroconvulsive therapy (ECT) is the most effective acute treatment for severe depression, but widely held concerns about memory problems may limit its use.
To find out whether repeated or ...maintenance courses of ECT cause cumulative cognitive deterioration.
Analysis of the results of 10 years of cognitive performance data collection from patients who have received ECT. The 199 patients had a total of 498 assessments, undertaken after a mean of 15.3 ECT sessions (range 0-186). A linear mixed-effect regression model was used, testing whether an increasing number of ECT sessions leads to deterioration in performance.
The total number of previous ECT sessions had no effect on cognitive performance. The major factors affecting performance were age, followed by the severity of depression at the time of testing and the number of days since the last ECT session.
Repeated courses of ECT do not lead to cumulative cognitive deficits. This message is reassuring for patients, carers and prescribers who are concerned about memory problems and confusion during ECT.
Genetic associations involving both rare and common alleles have been reported for schizophrenia but there have been no systematic scans for rare recessive genotypes using fully phased trio data. ...Here, we use exome sequencing in 604 schizophrenia proband-parent trios to investigate the role of recessive (homozygous or compound heterozygous) nonsynonymous genotypes in the disorder. The burden of recessive genotypes was not significantly increased in probands at either a genome-wide level or in any individual gene after adjustment for multiple testing. At a system level, probands had an excess of nonsynonymous compound heterozygous genotypes (minor allele frequency, MAF ⩽ 1%) in voltage-gated sodium channels (VGSCs; eight in probands and none in parents, P = 1.5 × 10(-)(4)). Previous findings of multiple de novo loss-of-function mutations in this gene family, particularly SCN2A, in autism and intellectual disability provide biological and genetic plausibility for this finding. Pointing further to the involvement of VGSCs in schizophrenia, we found that these genes were enriched for nonsynonymous mutations (MAF ⩽ 0.1%) in cases genotyped using an exome array, (5585 schizophrenia cases and 8103 controls), and that in the trios data, synaptic proteins interacting with VGSCs were also enriched for both compound heterozygosity (P = 0.018) and de novo mutations (P = 0.04). However, we were unable to replicate the specific association with compound heterozygosity at VGSCs in an independent sample of Taiwanese schizophrenia trios (N = 614). We conclude that recessive genotypes do not appear to make a substantial contribution to schizophrenia at a genome-wide level. Although multiple lines of evidence, including several from this study, suggest that rare mutations in VGSCs contribute to the disorder, in the absence of replication of the original findings regarding compound heterozygosity, this conclusion requires evaluation in a larger sample of trios.
Bipolar disorder is a severe psychiatric disorder influenced by environmental and genetic factors. Genetic studies have implicated many variants in the disease's etiology but only few have been ...successfully replicated. We conducted a genome‐wide association study (GWAS) on bipolar disorder in the Bulgarian population followed by a replication study of the top 100 single nucleotide polymorphisms (SNPs) showing the smallest P values. The GWAS was performed on 188 bipolar disorder patients and 376 control subjects genotyped on the Illumina 550 platform. The replication study was conducted on 122 patients and 328 controls. Although our study did not show any association P value that achieved genome‐wide significance, and none of the top 100 SNPs reached the Bonferroni‐corrected P value in the replication study, the plausible involvement of some variants cannot be entirely discarded. Three polymorphisms, rs8099939 P = 2.12 × 10−6, odds ratio (OR) = 1.95, 95% confidence interval (CI) = 1.43–2.67 in GRIK5, rs6122972 (P = 3.11 × 10−6, OR = 2.02, 95% CI = 1.46–2.80) in PARD6B and rs2289700 (P = 9.14 × 10−6, OR = 2.13, 95% CI = 1.53–2.95) in CTSH remained associated at a similar level after Mantel–Haenszel test for combining the results from the genome‐wide and replication studies. A modest association was also detected for SNP rs1012053 (GWAS P = 4.50 × 10−2) in DGKH, which has already been reported as the most significant variant in a previous genome‐wide scan on bipolar disorder. However, further studies using larger datasets are needed to identify variants with smaller effects that contribute to the risk of bipolar disorder.
The serotonin transporter (5-HTT) is a candidate locus for aetiological involvement in affective disorders. Biochemical studies in suicides and depressed patients suggest that 5-HT uptake function is ...frequently reduced in affective illness. Furthermore, 5-HTT is targeted by widely used antidepressant drugs such as fluoxetine. We have performed an association study of a short variant of the 5-HTT-linked polymorphic region (5-HTTLPR), which restricts transcriptional activity of the 5-HTT promoter leading to low functional expression of the 5-HTT, in 454 patients with bipolar or unipolar affective disorder and 570 controls, derived from three European Centres (London, Milan and Würzburg). In all three centres, the frequency of the low activity allele was higher in patients than in controls (50% vs 45% in London, 45% vs 43% in Milan, 47% vs 40% in Würzburg). Although these differences were not individually significant, a stratified analysis of all three samples gave a significant overall odds ratio of 1.23 (95% confidence interval 1.02-1.49, P = 0.03). The excess of the homozygous low-activity genotype among the patients was even greater (odds ratio 1.53, 95% confidence interval 1.04-2.23, P = 0.02), suggesting partial recessively of the low-activity allele. Given the functional role of 5-HTT, our findings suggest that 5-HTTLPR-dependent variation in functional 5-HTT expression is a potential genetic susceptibility factor for affective disorders. If this finding is replicated, further work on genetic variants with low 5-HTT activity may facilitate the differential diagnosis of affective disorders, the assessment of suicidal behaviour, and the prediction of good clinical response to antidepressants.
Serotonin (5-HT) neurotransmitter receptors are targeted by atypical antipsychotic drugs. We hypothesized that genetic variation in these receptors may affect clinical response to the drugs targeting ...them. This hypothesis has been tested by several studies in which the correlation between polymorphic variants in the 5-HT2A receptor gene and clinical response to the atypical antipsychotic clozapine was investigated. The results of these studies either found association between 5-HT2A genetic variants and clozapine response or found differences in the same direction which did not reach statistical significance. Meta-analysis of these studies including 373 patients who responded to the treatment and 360 non-responders showed association between two 5-HT2A polymorphisms, 102-T/C and His452Tyr, and clozapine response. Statistical analysis of extreme responders showed a clearer association of the 102-T/C with clozapine response. These results reinforce the hypothesis and strengthen the candidacy of these receptors as important therapeutic targets.
Bipolar affective disorder (BPAD) is a common psychiatric disorder with complex genetic aetiology. We have undertaken a genome-wide scan in one of the largest samples of bipolar affected sibling ...pairs (ASPs) using a two-stage approach combining sample splitting and marker grid tightening. In this second stage analysis, we have examined 17 regions that achieved a nominally significant maximum likelihood LOD score (MLS) threshold of 0.74 (or 1.18 for the X-chromosome) in stage one. The second stage has added 135 ASP families to bring the total stage 2 sample to 395 ASPs. In total, 494 microsatellite markers have been used to screen the human genome at a density of 10 cM in the first stage sample (260 ASPs) and 5 cM in the second stage. Under the broad diagnostic model, two markers gave LOD scores exceeding 3 with two-point analysis: D4S392 (LOD=3.30) and D10S197 (LOD=3.18). Multipoint analysis demonstrated suggestive evidence of linkage between BPAD and chromosomal regions 6q16-q21 (MLS=2.61) and 4q12-q21 (MLS=2.38). 6q16-q21 is of particular interest because our data, together with those from two recent genome scans, make this the best supported linkage region in BPAD. Further, our data show evidence of a gender effect at this locus with increased sharing predominantly within the male-male pairs. Our scan also provides support for linkage (MLS> or =1.5) at several other regions that have been implicated in meta-analyses of bipolar disorder and/or schizophrenia including 9p21, 10p14-p12 and 18q22.
We earlier reported a genome-wide significant linkage to schizophrenia at chromosome 17 that was identified in a single pedigree (C702) consisting of six affected, male siblings with DSM-IV ...schizophrenia and prominent mood symptoms. In this study, we adopted several approaches in an attempt to map the putative disease locus. First, mapping the source of linkage to chromosome 17 in pedigree C702. We refined the linkage region in family C702 to a 21-marker segment spanning 11.7 Mb at 17q23-q24 by genotyping a total of 50 microsatellites across chromosome 17 in the pedigree. Analysis of data from 1028 single nucleotide polymorphisms (SNPs) across the refined linkage region identified a single region of homozygosity present in pedigree C702 but not in 2938 UK controls. This spanned ~432 kb of the gene encoding protein kinase C, alpha (PRKCA), the encoded protein of which has been implicated in the pathogenesis of psychiatric disorders. Analysis of pedigree C702 by oligonucleotide-array comparative genome hybridization excluded the possibility that this region of homozygosity was because of a deletion. Mutation screening of PRKCA identified a rare, four-marker haplotype (C-HAP) in the 3' untranslated region of the gene, which was present in the homozygous state in all six affected members of pedigree C702. No other homozygotes were observed in genotype data for a total of 6597 unrelated Europeans (case N=1755, control N=3580 and parents of probands N=1262). Second, association analysis of C702 alleles at PRKCA. The low-frequency haplotype (C-HAP) showed a trend for association in a study of unrelated schizophrenia cases and controls from the UK (661 cases, 2824 controls, P=0.078 and odd ratio (OR)=1.9) and significant evidence for association when the sample was expanded to include cases with bipolar (N=710) and schizoaffective disorder (N=50) (psychosis sample: 1421 cases, 2824 controls, P=0.037 and OR=1.9). Given that all the affected members of C702 are male, we also undertook sex-specific analyses. This revealed that the association was strongest in males for both schizophrenia (446 male cases, 1421 male controls, P=0.008 and OR=3.9) and in the broader psychosis group (730 male cases, 1421 male controls, P=0.008 and OR=3.6). Analysis of C-HAP in follow-up samples from Ireland and Bulgaria revealed no evidence for association in either the whole sample or in males alone, and meta-analysis of all male psychosis samples yielded no significant evidence of association (969 male cases, 1939 male controls, 311 male probands P=0.304 and OR=1.4). Third, association mapping of the pedigree C702 linkage region. Independent of pedigree C702, genotype data from the Affymetrix 500k GeneChip set were available for 476 patients with schizophrenia and 2938 controls from the United Kingdom. SNPs in PRKCA showed evidence for association with schizophrenia that achieved gene-wide significance (P=0.027). Moreover, the same SNP was the most significantly associated marker out of the 1028 SNPs genotyped across the linkage region (rs873417, allelic P=0.0004). Follow-up genotyping in samples from Ireland, Bulgaria and Germany did not show consistent replication, but meta-analysis of all samples (4116 cases and 6491 controls) remained nominally significant (meta-analysis P=0.026, OR=1.1). We conclude that, although we have obtained convergent lines of evidence implicating both rare and common schizophrenia risk variants at PRKCA, none of these is individually compelling. However, the evidence across all approaches suggests that further study of this locus is warranted.
We report a kindred with euthyroid multi-nodular goitre (MNG) of adolescent onset. Two of the seven subjects with MNG have progressed to papillary thyroid cancer. One affected male had nodular kidney ...disease, and breast cancer occurred in one affected female. Genes that were candidates on the basis of the associated kidney (PAX8) and breast diseases (sodium iodide symporter (NIS)), were sequenced. No mutations were found in the coding region, intron/exon splice sites or in the promoter sequences (from -1248 relative to the translation initiation codon) of PAX8. Similar results were obtained for NIS. Subsequently, microsatellite analyses were performed on 14 informative family members. We used 2 to 3 markers per locus for 6 loci (on chromosomes 1,2,3,14,19,X) previously reported to predispose to MNG and/or familial non-medullary thyroid cancer (FNMTC). On the basis of non-significant logarithm of the odds ratio (LOD) scores or inheritance of different alleles in affected individuals, all loci have been excluded. Thyroidectomy specimens from three members of the kindred show multiple benign lesions, with papillary cancer in two. The morphological features do not resemble those seen in familial adenomatous polyposis, Cowden syndrome, or in multiple oxyphil lesions. From these findings and from the absence of any linkage to any of the known loci associated with MNG or FNMTC, we suggest that this represents a new form of inherited MNG with a significant risk of progression to papillary carcinoma.
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