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Background: Chlamydia abortus (formerly Chlamydophila abortus) is an economically important livestock pathogen, causing ovine enzootic abortion (OEA), and can also cause zoonotic infections in humans affecting pregnancy outcome. Large-scale genomic studies on other chlamydial species are giving insights into the biology of these organisms but have not yet been performed on C. abortus. Our aim was to investigate a broad collection of European isolates of C. abortus, using next generation sequencing methods, looking at diversity, geographic distribution and genome dynamics. Results: Whole genome sequencing was performed on our collection of 57 C. abortus isolates originating primarily from the UK, Germany, France and Greece, but also from Tunisia, Namibia and the USA. Phylogenetic analysis of a total of 64 genomes shows a deep structural division within the C. abortus species with a major clade displaying limited diversity, in addition to a branch carrying two more distantly related Greek isolates, LLG and POS. Within the major clade, seven further phylogenetic groups can be identified, demonstrating geographical associations. The number of variable nucleotide positions across the sampled isolates is significantly lower than those published for C. trachomatis and C. psittaci. No recombination was identified within C. abortus, and no plasmid was found. Analysis of pseudogenes showed lineage specific loss of some functions, notably with several Pmp and TMH/Inc proteins predicted to be inactivated in many of the isolates studied. Conclusions: The diversity within C. abortus appears to be much lower compared to other species within the genus. There are strong geographical signatures within the phylogeny, indicating clonal expansion within areas of limited livestock transport. No recombination has been identified within this species, showing that different species of Chlamydia may demonstrate different evolutionary dynamics, and that the genome of C. abortus is highly stable. [ABSTRACT FROM AUTHOR]

BackgroundStrategies to dissect phenotypic and genetic heterogeneity of major depressive disorder (MDD) have mainly relied on subphenotypes, such as age at onset (AAO) and recurrence/episodicity. Yet, evidence on whether these subphenotypes are familial or heritable is scarce. The aims of this study are to investigate the familiality of AAO and episode frequency in MDD and to assess the proportion of their variance explained by common single nucleotide polymorphisms (SNP heritability).MethodFor investigating familiality, we used 691 families with 2–5 full siblings with recurrent MDD from the DeNt study. We fitted (square root) AAO and episode count in a linear and a negative binomial mixed model, respectively, with family as random effect and adjusting for sex, age and center. The strength of familiality was assessed with intraclass correlation coefficients (ICC). For estimating SNP heritabilities, we used 3468 unrelated MDD cases from the RADIANT and GSK Munich studies. After similarly adjusting for covariates, derived residuals were used with the GREML method in GCTA (genome-wide complex trait analysis) software.ResultsSignificant familial clustering was found for both AAO (ICC = 0.28) and episodicity (ICC = 0.07). We calculated from respective ICC estimates the maximal additive heritability of AAO (0.56) and episodicity (0.15). SNP heritability of AAO was 0.17 (p = 0.04); analysis was underpowered for calculating SNP heritability of episodicity.ConclusionsAAO and episodicity aggregate in families to a moderate and small degree, respectively. AAO is under stronger additive genetic control than episodicity. Larger samples are needed to calculate the SNP heritability of episodicity. The described statistical framework could be useful in future analyses. [ABSTRACT FROM PUBLISHER]

It would be beneficial to find genetic predictors of antidepressant response to help personalise treatment of major depressive disorder (MDD). Rare copy number variants (CNVs) have been implicated in several psychiatric disorders, including MDD, but their role in antidepressant response has yet to be investigated. CNV data were available for 1565 individuals with MDD from the NEWMEDS (Novel Methods leading to New Medications in Depression and Schizophrenia) consortium with prospective data on treatment outcome with either a serotonergic or noradrenergic antidepressant. No association was seen between the presence of CNV (rare or common), the overall number of CNVs or genomic CNV 'burden' and antidepressant response. Specific CNVs were nominally associated with antidepressant response, including 15q13.3 duplications and exonic NRXN1 deletions. These were associated with poor response to antidepressants. Overall burden of CNVs is unlikely to contribute to personalising antidepressant treatment. Specific CNVs associated with antidepressant treatment require replication and further study to confirm their role in the therapeutic action of antidepressant. [ABSTRACT FROM AUTHOR]

Large, rare copy number variants (CNVs) have been implicated in a variety of psychiatric disorders, but the role of CNVs in recurrent depression is unclear. We performed a genome-wide analysis of large, rare CNVs in 3106 cases of recurrent depression, 459 controls screened for lifetime-absence of psychiatric disorder and 5619 unscreened controls from phase 2 of the Wellcome Trust Case Control Consortium (WTCCC2). We compared the frequency of cases with CNVs against the frequency observed in each control group, analysing CNVs over the whole genome, genic, intergenic, intronic and exonic regions. We found that deletion CNVs were associated with recurrent depression, whereas duplications were not. The effect was significant when comparing cases with WTCCC2 controls (P=7.7 × 10−6, odds ratio (OR) =1.25 (95% confidence interval (CI) 1.13-1.37)) and to screened controls (P=5.6 × 10−4, OR=1.52 (95% CI 1.20-1.93). Further analysis showed that CNVs deleting protein coding regions were largely responsible for the association. Within an analysis of regions previously implicated in schizophrenia, we found an overall enrichment of CNVs in our cases when compared with screened controls (P=0.019). We observe an ordered increase of samples with deletion CNVs, with the lowest proportion seen in screened controls, the next highest in unscreened controls and the highest in cases. This may suggest that the absence of deletion CNVs, especially in genes, is associated with resilience to recurrent depression. [ABSTRACT FROM AUTHOR]

There is evidence that obesity-related disorders are increased among people with depression. Variation in the FTO (fat mass and obesity associated) gene has been shown to contribute to common forms of human obesity. This study aimed to investigate the genetic influence of polymorphisms in FTO in relation to body mass index (BMI) in two independent samples of major depressive disorder (MDD) cases and controls. We analysed 88 polymorphisms in the FTO gene in a clinically ascertained sample of 2442 MDD cases and 809 controls (Radiant Study). In all, 8 of the top 10 single-nucleotide polymorphisms (SNPs) showing the strongest associations with BMI were followed-up in a population-based cohort (PsyCoLaus Study) consisting of 1292 depression cases and 1690 controls. Linear regression analyses of the FTO variants and BMI yielded 10 SNPs significantly associated with increased BMI in the depressive group but not the control group in the Radiant sample. The same pattern was found in the PsyCoLaus sample. We found a significant interaction between genotype and affected status in relation to BMI for seven SNPs in Radiant (P<0.0057), with PsyCoLaus giving supportive evidence for five SNPs (P-values between 0.03 and 0.06), which increased in significance when the data were combined in a meta-analysis. This is the first study investigating FTO and BMI within the context of MDD, and the results indicate that having a history of depression moderates the effect of FTO on BMI. This finding suggests that FTO is involved in the mechanism underlying the association between mood disorders and obesity. [ABSTRACT FROM AUTHOR]

BackgroundSymptom dimensions have not yet been comprehensively tested as predictors of the substantial heterogeneity in outcomes of antidepressant treatment in major depressive disorder.MethodWe tested nine symptom dimensions derived from a previously published factor analysis of depression rating scales as predictors of outcome in 811 adults with moderate to severe depression treated with flexibly dosed escitalopram or nortriptyline in Genome-based Therapeutic Drugs for Depression (GENDEP). The effects of symptom dimensions were tested in mixed-effect regression models that controlled for overall initial depression severity, age, sex and recruitment centre. Significant results were tested for replicability in 3637 adult out-patients with non-psychotic major depression treated with citalopram in level I of Sequenced Treatment Alternatives to Relieve Depression (STAR*D).ResultsThe interest-activity symptom dimension (reflecting low interest, reduced activity, indecisiveness and lack of enjoyment) at baseline strongly predicted poor treatment outcome in GENDEP, irrespective of overall depression severity, antidepressant type and outcome measure used. The prediction of poor treatment outcome by the interest-activity dimension was robustly replicated in STAR*D, independent of a comprehensive list of baseline covariates.ConclusionsLoss of interest, diminished activity and inability to make decisions predict poor outcome of antidepressant treatment even after adjustment for overall depression severity and other clinical covariates. The prominence of such symptoms may require additional treatment strategies and should be accounted for in future investigations of antidepressant response. [ABSTRACT FROM PUBLISHER]

Suicidal thoughts during antidepressant treatment have been the focus of several candidate gene association studies. The aim of the present genome-wide association study was to identify additional genetic variants involved in increasing suicidal ideation during escitalopram and nortriptyline treatment. A total of 706 adult participants of European ancestry, treated for major depression with escitalopram or nortriptyline over 12 weeks in the Genome-Based Therapeutic Drugs for Depression (GENDEP) study were genotyped with Illumina Human 610-Quad Beadchips (Illumina, San Diego, CA, USA). A total of 244 subjects experienced an increase in suicidal ideation during follow-up. The genetic marker most significantly associated with increasing suicidality (8.28 × 10−7) was a single-nucleotide polymorphism (SNP; rs11143230) located 30 kb downstream of a gene encoding guanine deaminase (GDA) on chromosome 9q21.13. Two suggestive drug-specific associations within KCNIP4 (Kv channel-interacting protein 4; chromosome 4p15.31) and near ELP3 (elongation protein 3 homolog; chromosome 8p21.1) were found in subjects treated with escitalopram. Suggestive drug by gene interactions for two SNPs near structural variants on chromosome 4q12, one SNP in the apolipoprotein O (APOO) gene on chromosome Xp22.11 and one on chromosome 11q24.3 were found. The most significant association within a set of 33 candidate genes was in the neurotrophic tyrosine kinase receptor type 2 (NTRK2) gene. Finally, we also found trend for an association within genes previously associated with psychiatric phenotypes indirectly linked to suicidal behavior, that is, GRIP1, NXPH1 and ANK3. The results suggest novel pathways involved in increasing suicidal ideation during antidepressant treatment and should help to target treatment to reduce the risk of this dramatic adverse event. Limited power precludes definitive conclusions and replication in larger sample is warranted. [ABSTRACT FROM AUTHOR]

BackgroundCognitive impairment, particularly in memory and executive function, is a core feature of psychosis. Moreover, psychosis is characterized by a more prominent history of stress exposure, and by dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis. In turn, stress exposure and abnormal levels of the main HPA axis hormone cortisol are associated with cognitive impairments in a variety of clinical and experimental samples; however, this association has never been examined in first-episode psychosis (FEP).MethodIn this study, 30 FEP patients and 26 controls completed assessment of the HPA axis (cortisol awakening response and cortisol levels during the day), perceived stress, recent life events, history of childhood trauma, and cognitive function. The neuropsychological battery comprised general cognitive function, verbal and non-verbal memory, executive function, perception, visuospatial abilities, processing speed, and general knowledge.ResultsPatients performed significantly worse on all cognitive domains compared to controls. In patients only, a more blunted cortisol awakening response (that is, more abnormal) was associated with a more severe deficit in verbal memory and processing speed. In controls only, higher levels of perceived stress and more recent life events were associated with a worse performance in executive function and perception and visuospatial abilities.ConclusionsThese data support a role for the HPA axis, as measured by cortisol awakening response, in modulating cognitive function in patients with psychosis; however, this association does not seem to be related to the increased exposure to psychosocial stressors described in these patients. [ABSTRACT FROM PUBLISHER]

Background. Response and remission defined by cut-off values on the last observed depression severity score are commonly used as outcome criteria in clinical trials, but ignore the time course of symptomatic change and may lead to inefficient analyses. We explore alternative categorization of outcome by naturally occurring trajectories of symptom change. Method. Growth mixture models were applied to repeated measurements of depression severity in 807 participants with major depression treated for 12 weeks with escitalopram or nortriptyline in the part-randomized Genome-based Therapeutic Drugs for Depression study. Latent trajectory classes were validated as outcomes in drug efficacy comparison and pharmacogenetic analyses. Results. The final two-piece growth mixture model categorized participants into a majority (75%) following a gradual improvement trajectory and the remainder following a trajectory with rapid initial improvement. The rapid improvement trajectory was over-represented among nortriptyline-treated participants and showed an antidepressant-specific pattern of pharmacogenetic associations. In contrast, conventional response and remission favoured escitalopram and produced chance results in pharmacogenetic analyses. Controlling for drop-out reduced drug differences on response and remission but did not affect latent trajectory results. Conclusions. Latent trajectory mixture models capture heterogeneity in the development of clinical response after the initiation of antidepressants and provide an outcome that is distinct from traditional endpoint measures. It differentiates between antidepressants with different modes of action and is robust against bias due to differential discontinuation. [ABSTRACT FROM AUTHOR]

The tricyclic antidepressant (TCA) clomipramine has been widely used in psychiatry for over 40 years. More recently, its therapeutic potential as an antineoplastic drug has been identified. However, there are no prior data on regional distribution in the brain of clomipramine and its primary metabolite (desmethylclomipramine) after chronic oral administration. The aim of this study was to determine the concentrations of clomipramine and desmethylclomipramine in different rat-brain regions and to compare those with levels in plasma and peripheral organs after chronic oral treatment of Sprague Dawley rats (15 mg/kg) for 14 days. The levels of both parent TCA and metabolite were analysed by high-performance liquid chromatography in six brain regions (cortex, hypothalamus, hippocampus, striatum, brainstem and cerebellum), five peripheral organs and in plasma. Our data show that the cerebral cortex had the highest concentration of clomipramine (2.9 µg/mg), with successively lower concentrations in the hypothalamus, striatum, cerebellum, hippocampus and brainstem. Of the peripheral organs, the lungs and liver, had the highest levels of clomipramine, while in the heart, only the metabolite was detected. The plasma concentration (0.17 µg/ml or 0.48 µM) was comparable to that in the hippocampus and cerebellum (approximately 0.20 µg/mg). The differential distribution of clomipramine in different brain regions and the regional variation in clomipramine to desmethylclomipramine ratios have implications for the use of clomipramine in psychiatry and neuro-oncology. [ABSTRACT FROM AUTHOR]

Quantitative real-time polymerase chain reaction (PCR) is an effective approach in investigating the effects of exogenous compounds on gene expression. This is often achieved by exploiting so-called 'housekeeping' genes as baseline controls to normalise expression levels, which have historically been assumed to have a relatively stable expression pattern. Recent non-in-vitro studies have questioned the validity of this, but previous in-vitro data were lacking following antidepressant treatment. We here investigated the stability of 12 housekeeping genes during treatment of the mouse L929 fibroblast cell line with escitalopram and nortriptyline. Cells were cultured in the presence of antidepressant at 1 µM or 10 µM for 30 min, 24 h or 48 h, and RNA subjected to quantitative PCR (qPCR). Stability of relative transcript expression values was assessed via gene-gene expression ratios and intra- and inter-group variation (using geNorm and NormFinder programs). The three most stable transcripts were adenosine triphosphate (ATP) synthase, H+ transporting mitochondrial F1 complex, β subunit, β-2 microglobulin and cytochrome c-1. The least stable were Gapdh, eukaryotic translation initiation factor 4A2 and Calnexin (Canx). In conclusion, care must be taken when choosing reference transcripts for analysis in qPCR. For in-vitro pharmacological studies, it should not be assumed that 'housekeeping' genes are stable. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the 8th Annual Pharmacogenetics in Psychiatry Meeting held in New York City. An association study of candidate genes with obesity phenotypes in schizophrenics was presented by Yvon Chagnon. Daniel Mueller of the University of Toronto provided data on the cannabinoid-1 receptor and dopamine receptor gene on weight gain. Meanwhile, Holly Garriock of the University of California presented a genome-wide study of intolerance to citalopram in the Sequenced Treatment Alternatives for Depression sample of individuals.

Depression and fatigue are frequent side effects of interferon-α (IFN-α) treatment, and there is compelling evidence that the inflammatory response system (including interleukin-6, IL-6) and the serotonergic system is important in the pathophysiology of such symptoms. Functional polymorphisms in the promoter region of the IL-6 gene (rs1800795) and serotonin transporter gene (5-HTTLPR) have been identified as regulating these systems. The present study aimed to determine if these polymorphisms were associated with the development of depression and fatigue during IFN-α and ribavirin treatment. Ninety-eight Caucasian patients receiving pegylated IFN-α and ribavirin treatment for chronic hepatitis C virus at King's College Hospital, London, and Emory University Hospital, Atlanta, participated in this prospective cohort study. Symptoms of depression and fatigue were measured before treatment and at weeks 4, 8, 12 and 24 during treatment. The ‘low IL-6’ synthesizing genotype (CC) was associated with significantly fewer symptoms of depression (effect size=0.7 at week 24; F=9.4, d.f.=436, P=0.002). The ‘high transcription’ serotonin transporter (5-HTT) genotype (LL) was also associated with significantly fewer symptoms of depression, but with a much smaller effect (effect size=0.2 at week 24; F=4.5, d.f.=436, P=0.03). Neither polymorphisms were associated with symptoms of fatigue (IL-6: F=1.2, d.f.=430, P=0.2; 5-HTT: F=0.5, d.f.=430, P=0.5). The smaller effects of the 5-HTT polymorphism on depression may be explained by an interaction between the genes (F=5.0, d.f.=434, P=0.02): the ‘protective’ effect of the 5-HTTLPR polymorphism was evident only in the presence of the ‘low IL-6’ genotype (F=5.4, d.f.=64, P=0.02), not in the presence of the ‘high IL-6’ genotype (F=2.2, d.f.=369, P=0.1). The association between the IL-6 polymorphism and reduced risk of depressive symptoms confirms the role of the inflammatory response system in the pathophysiology of IFN-α-induced depression; in contrast, the effect of the 5-HTT gene was small and perhaps dependent on the status of the inflammatory response. [ABSTRACT FROM AUTHOR]

There is significant unmet need for more effective treatments for bipolar disorder. The drug discovery process is becoming prohibitively expensive. Hence, biomarker clues to assist or shortcut this process are now widely sought. Using the publicly available data from the whole genome association study conducted by the Wellcome Trust Case Control Consortium, we sought to identify groups of genetic markers (single nucleotide polymorphisms) in which each marker was independently associated with bipolar disorder, with a less stringent threshold than that set by the original investigators (p⩽1 ×10-4). We identified a group of markers occurring within the CACNA1C gene (encoding the alpha subunit of the calcium channel Cav1.2). We then ascertained that this locus had been previously associated with the disorder in both a smaller and a whole genome study, and that a number of drugs blocking this channel (including verapamil and diltiazem) had been trialled in the treatment of bipolar disorder. The dihydropyridine-based blockers such as nimodipine that bind specifically to Cav1.2 and are more penetrant to the central nervous system have shown some promising early results; however, further trials are indicated. In addition, migraine is commonly seen in affective disorder, and calcium channel antagonists are successfully used in the treatment of migraine. One such agent, flunarizine, is structurally related to other first-generation derivatives of antihistamines such as antipsychotics. This implies that flunarizine could be useful in the treatment of bipolar disorder, and, furthermore, that other currently licensed drugs should be investigated for antagonism of Cav1.2. [ABSTRACT FROM AUTHOR]

Aripiprazole has recently received approval for the treatment of moderate to severe manic episodes in bipolar I disorder and prevention of new manic episodes in aripiprazole-responsive patients. Aripiprazole differs from other antipsychotics in its pharmacology, and the need for prescribing guidance in the UK was recently identified. A UK multidisciplinary panel was convened in November 2007. This report describes the consensus agreed during the meeting on the optimal approach to prescribing aripiprazole: how best to approach initiation of, and switching to, treatment with aripiprazole and management strategies for side effects. A literature review of the randomised controlled clinical trials of aripiprazole in mania supports these recommendations. Aripiprazole should be initiated at 15 mg/day (range 5-20 mg/day). If necessary, adjunctive medication should be used in early treatment to manage side effects or assist in management of symptoms such as agitation. When switching to aripiprazole, the therapeutic dose of current treatment should be maintained while adding aripiprazole 15 (5-20) mg/day. Only once an effective dose of aripiprazole is reached should previous medication be reduced. Nausea, insomnia and agitation typically resolve within days. Some principles for dosing and switching are provided to assist with a successful treatment outcome with aripiprazole in mania. [ABSTRACT FROM AUTHOR]

The Antipsychotic Non-Neurological Side-Effects Rating Scale (ANNSERS) was developed to provide a comprehensive measure for rating non-neurological adverse drug reactions (ADRs) to antipsychotics. Although there were already available measures that adequately rated specific non-neurological ADRs, such as sexual side effects, a need was identified for a scale that comprehensively rated the full range of non-neurological ADRs commonly seen across the spectrum of first and second generation antipsychotic drugs, including metabolic and autonomic ADRs. This article reports on work to establish the interrater reliability of an early version and a later, more comprehensive version of the ANNSERS (versions 1 and 2, v1 and v2, respectively). The measures were administered in London centres to patients treated with clozapine. Trained clinicians rated the patients simultaneously and independently. Interrater reliability on the scores was calculated using the kappa coefficient method. The results (mean kappa coefficients of 0.77 and 0.72, respectively) indicate that substantial interrater reliability was achieved for both versions. Items for which the main basis for rating was laboratory investigations rather than patient interview were largely excluded from this study, and kappas were also not calculated for items with a low frequency (less than 10%) of endorsement. Samples of patients on other antipsychotics would be required to reliably calculate kappa coefficients for these items. In conclusion, the ANNSERS represents a clinically applicable research innovation, with good interrater reliability on clinician judged items, which is now available for the comprehensive assessment of non-neurological ADRs to antipsychotics, to aid the processes of clinical audit, research and drug discovery. [ABSTRACT FROM AUTHOR]

Despite the common use of MDMA (ecstasy) in the UK, the mechanism underlying associated potentially fatal cerebral oedema is unclear. We used a new experimental approach working directly with dubbers to perform a study on 30 (17 male) experienced dubbers (mean 6.6 years of dubbing). Pre- and post clubbing measurements were performed to compare plasma levels of pituitary hormones (vasopressin, oxytocin), plasma and urine osmolality, urinary pH, and plasma sodium and urea. Ecstasy consumption was confirmed by using urinary drug screening pre- and post-clubbing. MDMA was detected in the urine samples of 17 subjects, three of which tested positive during pre-clubbing tests. Mean plasma vasopressin concentration increased in the MDMA group (1.28 ± 0.29 to 143 ± 0.41 pmol/l), but fell in other participants (1.23 ± 0.42 to 1.16 ± 0.0.34 pmol/l). Similarly, mean plasma oxytocin concentrations increased after ingestion of MDMA (2.02 ± 0.29 to 243 ± 0.24 pmol/l), but fell in the group that did not use MDMA (2.17 ± 0.36 pmol/l to 1.89 ± 0.37pmol/l). There was a significant group by time interaction for plasma osmolality and plasma sodium (p = 0.001 and p = 0.003, respectively) and between change in urinary osmolality (p<0.001) and MDMA use, with the pattern of change being consistent with the induction of inappropriate vasopressin secretion (also known as SIADH) by MDMA. This report demonstrates SIADH in ecstasy-using 'clubbers', which has important clinical implications. [ABSTRACT FROM AUTHOR]

The aim of this study was to use the CYP1A2-null mouse to investigate the in-vivo contribution of CYP1A2 to clozapine pharmacokinetics and pharmacodynamics. An intraperitoneal injection of 10 mg/kg clozapine was administered to four male CYP1A2 -/- mice and four male wild-type mice. Clozapine, desmethylclozapine, and clozapine N-oxide concentrations in sequential tail blood samples were measured by HPLC with UV detection. Behavioural parameters were recorded at each time point. The area under the curve (AUC) of clozapine was 2.6 times greater, the clearance of clozapine was 2.6 times slower, and the half-life was 1.2 times longer in the CYP1A2 -/- mice (p = 0.0143) as compared to the wild-type mice. Sixty-one percent of the clozapine clearance in wild-type mice was calculated to be mediated by CYP1A2. The AUC of desmethylclozapine was 1.6 times lower in the CYP1A2 -/- mice compared to the wild-type mice (p = 0.0286), while there was a trend for the AUC of clozapine N-oxide to be greater in the CYP1A2 -/- mice (p = 0.0571). The CYP1A2 -/- mice were significantly more drowsy and showed more motor impairment (p = 0.0145) and myoclonus than the wild-type mice. Our results indicate that, in vivo, CYP1A2 is the major determinant of clozapine clearance, contributes significantly to the demethylation of clozapine, and has a negligible contribution to the N-oxidation. Our data also indicate that CYP1A2 poor metabolizers might be more susceptible than extensive metabolizers to dose-related adverse effects of clozapine, such as sedation, myoclonus and seizures. [ABSTRACT FROM AUTHOR]

Background: Schizophrenia is highly expensive in calculable and incalculable costs. Measures which impact the cost in the most severely affected are likely to produce the greatest cost reductions. Studies regarding clozapine in the USA have demonstrated clear cost-effectiveness, despite the high prescription costs. There are no prior UK studies.Method: We performed a cost-effectiveness analysis comparing the three years prior to commencing clozapine to the period following establishment of clozapine treatment (mean 36.4 months) for 26 patients with chronic schizophrenia or schizoaffective disorder.Results: There was a significant improvement in all clinical ratings applied (and a mean net saving of ponds 3768 per annum). The cost-effectiveness of clozapine was double that of conventional neuroleptics (15.2 pre-, 33.0 post-clozapine, P < 0.005).Conclusions: As a naturalistic study our data provide valuable information on the cost-effectiveness of clozapine in the UK. Our methodology could be applied in a community setting or in the study of another atypical neuroleptic. [ABSTRACT FROM AUTHOR]

We examined a Ser-9-Gly polymorphism in the dopamine D3 receptor gene for allelic association with schizophrenia in 133 patients currently treated with clozapine and 109 controls. Allele 1 (Ser-9) was significantly more frequent in the patients (69%) than in the controls (56%) ( P = 0.004). The 1-1 genotype was more common (43% vs 30%) and the 2-2 genotype less common (5% vs 18%) in patients than in controls. When the patient group was subdivided on the basis of clinical response to clozapine, using a 20-point improvement in the global assessment scale as cut-off, genotype 1-1 was found to be more frequent among the non-responders (53% vs 36%, P = 0.04). To place our results in the context of previous studies of this polymorphism and schizophrenia, we performed a meta-analysis of all published data including the present sample. The combined analysis shows evidence for a modest association between genotype 1-1 and schizophrenia (odds ratio 1.25, 95% confidence interval 1.05-1:49, P = 0.01). These results suggest that the Ser-9 allele, or a nearby polymorphism in linkage disequilibrium, results in a small increase in susceptibility to schizophrenia. [ABSTRACT FROM AUTHOR]

A correction to the article "Functional Polymorphisms in the Interleukin-6 and Serotonin Transporter Genes and Depression and Fatigue Induced by Interferon-α and Ribavirin Treatment" that was published in the January 12, 2009 issue is presented.

A letter to the editor is presented in response to a commentary about the article "Establishing cost-effectiveness of atypical neuroleptics," by G. Robert and P. Kennedy.