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Acquired or de novo resistance to poly (ADP-ribose) polymerase inhibitors (PARPi) is a major challenge to ovarian cancer treatment. Therefore, strategies to overcome PARPi resistance are critical to improve prognosis. The purpose of this study is to evaluate whether inhibition of ADAM17 sensitizes ovarian cancer to treatment with olaparib, a PARPi, thereby bypassing resistance mechanisms and improving treatment response. Thus, we analyzed the effect of olaparib in combination with the ADAM17 inhibitor GW280264X in ovarian cancer using a 2D monolayer and a 3D spheroid model followed by a multicontent readout (viability, caspase activation and cytotoxicity). To emphasize the translational aspect of our work, we performed corresponding experiments on primary cells derived from ovarian cancer patients initially screened for their mutation status of the breast cancer gene (BRCA 1/2). In 2D, we observed a significant reduction in cell viability and a subsequent increase in apoptosis of the combined treatment (olaparib + GW280264X) compared with olaparib mono-treatment. The combined treatment allows a substantial dose reduction of olaparib rendering a strong synergistic effect. Using a 3D spheroid model from primary cells, we confirmed the 2D monoculture results and demonstrated not only increased caspase activity under the combined treatment but also a substantial gain in cytotoxicity compared to the mono-treatment. Our study proposes ADAM17 inhibition sensitizing ovarian cancer to olaparib treatment and improving treatment response. [ABSTRACT FROM AUTHOR]

In vitro, spheroid models have become well established in cancer research because they can better mimic certain characteristics of in vivo tumours. However, interaction with the tumour microenvironment, such as cancer-associated fibroblasts, plays a key role in tumour progression. We initially focused on the interaction of tumour cells with fibroblasts. To model this interaction, we developed a spheroid model of ovarian cancer and fibroblasts. To this end, ovarian cancer cell lines and ex vivo primary cells were simultaneously and sequentially seeded with fibroblasts in a scaffold-free system at different ratios and subsequently characterized with respect to changes in morphology, proliferation, and viability. We demonstrated that co-cultures are able to form by far more compact spheroids, especially in cells that form aggregates in mono-culture. In addition, the co-cultures were able to increase proliferation and sensitivity to cisplatin. Simultaneous seeding led fibroblasts invade the core in both cell lines and primary cells. These results show differences in formation, firmness, and size between co-culture and mono-culture. Our model is designed to better represent and characterize the mutual influencing factors of fibroblasts and tumour cells. Fibroblast-supplemented multicellular spheroids are a valuable tool for tumour microenvironment interaction and new drug discovery. [ABSTRACT FROM AUTHOR]

Recent studies reported an impact of the melanocortin 3 receptor (MC3R) on the regulation of body weight, linear growth and puberty timing. Previously, allele p.44Ile of a frequent non-synonymous variant (NSV) p.Val44Ile was reported to be associated with decreased lean body mass (LBM) and later puberty in both sexes. We Sanger sequenced the coding region of MC3R in 185 children or adolescents with short normal stature (SNS) or 258 individuals with severe obesity, and 192 healthy-lean individuals. Eleven variants (six NSVs) were identified. In-silico analyses ensued. Three rare loss-of-function (LoF) variants (p.Phe45Ser, p.Arg220Ser and p.Ile298Ser) were only found in severely obese individuals. One novel highly conserved NSV (p.Ala214Val), predicted to increase protein stability, was detected in a single lean female. In the individuals with SNS, we observed deviation from Hardy–Weinberg Equilibrium (HWE) (p = 0.012) for p.Val44Ile (MAF = 11.62%). Homozygous p.44Ile carriers with SNS had an increased BMI, but this effect did not remain significant after Bonferroni correction. In line with previous findings, the detected LoF NSVs may suggest that dysfunction in MC3R is associated with decreased body height, obesity and delayed puberty. [ABSTRACT FROM AUTHOR]

Transcranial Direct Current Stimulation (tDCS) is a non-invasive neuromodulation technique with a wide variety of clinical and research applications. As increasingly acknowledged, its effectiveness is subject dependent, which may lead to time consuming and cost ineffective treatment development phases. We propose the combination of electroencephalography (EEG) and unsupervised learning for the stratification and prediction of individual responses to tDCS. A randomized, sham-controlled, double-blind crossover study design was conducted within a clinical trial for the development of pediatric treatments based on tDCS. The tDCS stimulation (sham and active) was applied either in the left dorsolateral prefrontal cortex or in the right inferior frontal gyrus. Following the stimulation session, participants performed 3 cognitive tasks to assess the response to the intervention: the Flanker Task, N-Back Task and Continuous Performance Test (CPT). We used data from 56 healthy children and adolescents to implement an unsupervised clustering approach that stratify participants based on their resting-state EEG spectral features before the tDCS intervention. We then applied a correlational analysis to characterize the clusters of EEG profiles in terms of participant's difference in the behavioral outcome (accuracy and response time) of the cognitive tasks when performed after a tDCS-sham or a tDCS-active session. Better behavioral performance following the active tDCS session compared to the sham tDCS session is considered a positive intervention response, whilst the reverse is considered a negative one. Optimal results in terms of validity measures was obtained for 4 clusters. These results show that specific EEG-based digital phenotypes can be associated to particular responses. While one cluster presents neurotypical EEG activity, the remaining clusters present non-typical EEG characteristics, which seem to be associated with a positive response. Findings suggest that unsupervised machine learning can be successfully used to stratify and eventually predict responses of individuals to a tDCS treatment. [ABSTRACT FROM AUTHOR]

Epidemiological studies have shown that gestational age and birth weight are linked to cognitive performance in adults. On a neurobiological level, this effect is hypothesized to be related to cortical gyrification, which is determined primarily during fetal development. The relationships between gestational age, gyrification and specific cognitive abilities in adults are still poorly understood. In 542 healthy participants, gyrification indices were calculated from structural magnetic resonance imaging T1 data at 3 T using CAT12. After applying a battery of neuropsychological tests, neuropsychological factors were extracted with a factor analysis. We conducted regressions to test associations between gyrification and gestational age as well as birth weight. Moderation analyses explored the relationships between gestational age, gyrification and neuropsychological factors. Gestational age is significantly positively associated with cortical folding in the left supramarginal, bilaterally in the superior frontal and the lingual cortex. We extracted two neuropsychological factors that describe language abilities and working memory/attention. The association between gyrification in the left superior frontal gyrus and working memory/attention was moderated by gestational age. Further, the association between gyrification in the left supramarginal cortex and both, working memory/attention as well as language, were moderated by gestational age. Gyrification is associated with gestational age and related to specific neuropsychological outcomes in healthy adulthood. Implications from these findings for the cortical neurodevelopment of cognitive domains and mental health are discussed. [ABSTRACT FROM AUTHOR]

Methodological studies investigating transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (lDLPFC) in paediatric populations are limited. Therefore, we investigated in a paediatric population whether stimulation success of multichannel tDCS over the lDLPFC depends on concurrent task performance and individual head anatomy. In a randomised, sham-controlled, double-blind crossover study 22 healthy participants (10–17 years) received 2 mA multichannel anodal tDCS (atDCS) over the lDLPFC with and without a 2-back working memory (WM) task. After stimulation, the 2-back task and a Flanker task were performed. Resting state and task-related EEG were recorded. In 16 participants we calculated the individual electric field (E-field) distribution. Performance and neurophysiological activity in the 2-back task were not affected by atDCS. atDCS reduced reaction times in the Flanker task, independent of whether atDCS had been combined with the 2-back task. Flanker task related beta oscillation increased following stimulation without 2-back task performance. atDCS effects were not correlated with the E-field. We found no effect of multichannel atDCS over the lDLPFC on WM in children/adolescents but a transfer effect on interference control. While this effect on behaviour was independent of concurrent task performance, neurophysiological activity might be more sensitive to cognitive activation during stimulation. However, our results are limited by the small sample size, the lack of an active control group and variations in WM performance. [ABSTRACT FROM AUTHOR]

Case-only (CO) studies are a powerful means to uncover gene-environment (G × E) interactions for complex human diseases. Moreover, such studies may in principle also draw upon genotype imputation to increase statistical power even further. However, genotype imputation usually employs healthy controls such as the Haplotype Reference Consortium (HRC) data as an imputation base, which may systematically perturb CO studies in genomic regions with main effects upon disease risk. Using genotype data from 719 German Crohn Disease (CD) patients, we investigated the level of imputation accuracy achievable for single nucleotide polymorphisms (SNPs) with or without a genetic main effect, and with varying minor allele frequency (MAF). Genotypes were imputed from neighbouring SNPs at different levels of linkage disequilibrium (LD) to the target SNP using the HRC data as an imputation base. Comparison of the true and imputed genotypes revealed lower imputation accuracy for SNPs with strong main effects. We also simulated different levels of G × E interaction to evaluate the potential loss of statistical validity and power incurred by the use of imputed genotypes. Simulations under the null hypothesis revealed that genotype imputation does not inflate the type I error rate of CO studies of G × E. However, the statistical power was found to be reduced by imputation, particularly for SNPs with low MAF, and a gradual loss of statistical power resulted when the level of LD to the SNPs driving the imputation decreased. Our study thus highlights that genotype imputation should be employed with great care in CO studies of G × E interaction. [ABSTRACT FROM AUTHOR]

Genetic (G) and environmental (E) factors are involved in the etiology and course of the major psychoses (MP), i.e. major depressive disorder (MDD), bipolar disorder (BD), schizoaffective disorder (SZA) and schizophrenia (SZ). The neurobiological correlates by which these predispositions exert their influence on brain structure, function and course of illness are poorly understood. In the FOR2107 consortium, animal models and humans are investigated. A human cohort of MP patients, healthy subjects at genetic and/or environmental risk, and control subjects (N = 2500) has been established. Participants are followed up after 2 years and twice underwent extensive deep phenotyping (MR imaging, clinical course, neuropsychology, personality, risk/protective factors, biomaterials: blood, stool, urine, hair, saliva). Methods for data reduction, quality assurance for longitudinal MRI data, and (deep) machine learning techniques are employed. In the parallelised animal cluster, genetic risk was introduced by a rodent model (Cacna1c deficiency) and its interactions with environmental risk and protective factors are studied. The animals are deeply phenotyped regarding cognition, emotion, and social function, paralleling the variables assessed in humans. A set of innovative experimental projects connect and integrate data from the human and animal parts, investigating the role of microRNA, neuroplasticity, immune signatures, (epi-)genetics and gene expression. Biomaterial from humans and animals are analyzed in parallel. The FOR2107 consortium will delineate pathophysiological entities with common neurobiological underpinnings ("biotypes") and pave the way for an etiologic understanding of the MP, potentially leading to their prevention, the prediction of individual disease courses, and novel therapies in the future. [ABSTRACT FROM AUTHOR]

Platelet function might play an essential role in the pathogenesis of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (SAH). Thus, impaired platelet function and disturbed primary haemostasis induced by intake of acetylsalicylic acid (ASA) might influence the rate of DCI. Primary haemostasis and platelet function can be measured with in vitro diagnosis (platelet function analyser test, PFA 100). The aim of this study is to evaluate the rate of DCI, haemorrhagic complications and the neurological outcome. Two groups were compared (patients with regular platelet function versus patients with impaired platelet function). This is a retrospective observational study. An initial cohort of 787 patients with SAH has been treated from January 2005 to September 2012. Seventy-nine patients (10%) with aneurysmal SAH, a history of ASA medication and PFA testing within the first 24 h after aneurysm rupture have been included. The overall rate of DCI in the present study was 43%. In vitro platelet function testing showed pathological primary haemostasis in 69.6%. The DCI rate was higher in patients with regular tested primary haemostasis (p = 0.02, OR = 3.16, 95%CI = [1.19; 8.83]). However, outcome assessment by mGOS did not show a significant difference between the groups. Patients with impaired primary haemostasis did not display a higher rate of haemorrhagic complications. Impairment of primary haemostasis resulting from an impairment of platelet function at an early stage after SAH might lead to a lower rate of DCI. In vitro testing of platelet function might be useful to predict the occurrence of DCI in the course. [ABSTRACT FROM AUTHOR]

Background: Clinical outcome and mortality in intracerebral haemorrhage (ICH) associated with anticoagulant treatment is poor. Novel direct oral anticoagulant drugs (NOACs) are increasingly prescribed. Management of NOAC-associated ICH might be more challenging. The aim of this study was to compare the clinical and radiological course of ICH patients being treated with different forms of oral anticoagulant drugs. Method: The study is a retrospective observational study. Haemorrhage in other intracranial compartments except the ventricular system were explicitly excluded. Four groups were categorised and compared with regard to their clinical and radiological course (NOACs, vitamin K antagonists [VKAs], platelet inhibitors and patients without anticoagulant/antiplatelet drugs). Clinical as well as radiological parameters were analysed. Results: Overall, 182 patients were included (2011 to early 2016). Twenty-five patients with NOAC-associated ICH were included (47 with VKAs, 50 with platelet inhibitors and 60 patients without anticoagulant/antiplatelet drugs). The frequency of NOAC-associated ICH increased over the years. Diabetes was found significantly more often in the NOAC patients ( p = 0.05). The clinical and radiological courses in the three different patient groups with impaired coagulation were similar. Mortality was significantly higher in patient groups with impaired coagulation ( p = 0.04) compared to those without anticoagulant/antiplatelet drugs. Multivariate analysis revealed the Glasgow Coma Scale (GCS) score as a strong predictor for worse outcome and mortality. Conclusions: The frequency of NOAC-associated ICH increased in the last 5 years. Diabetes might be a risk factor for ICH when receiving NOACs. Clinical outcome in NOAC-associated ICH is poor and mortality is as high as in patients with other oral anticoagulant/antiplatelet drugs. [ABSTRACT FROM AUTHOR]

Elevated serum leptin levels following rapid therapeutically induced weight gain in anorexia nervosa (AN) patients are discussed as a potential biomarker for renewed weight loss as a result of leptin-related suppression of appetite and increased energy expenditure. This study aims to analyze the predictive value of leptin levels at discharge as well as the average rate of weight gain during inpatient or day patient treatment for body weight at 1-year follow-up. 121 patients were recruited from the longitudinal Anorexia Nervosa Day patient versus Inpatient (ANDI) trial. Serum leptin levels were analyzed at referral and discharge. A multiple linear regression analysis to predict age-adjusted body mass index (BMI-SDS) at 1-year follow-up was performed. Leptin levels, the average rate of weight gain, premorbid BMI-SDS, BMI-SDS at referral, age and illness duration were included as independent variables. Neither leptin levels at discharge nor rate of weight gain significantly predicted BMI-SDS at 1-year follow-up explaining only 1.8 and 0.4 % of the variance, respectively. According to our results, leptin levels at discharge and average rate of weight gain did not exhibit any value in predicting weight at 1-year follow-up in our longitudinal observation study of adolescent patients with AN. Thus, research should focus on other potential factors to predict weight at follow-up. As elevated leptin levels and average rate of weight gain did not pose a risk for reduced weight, we found no evidence for the beneficial effect of slow refeeding in patients with acute AN. [ABSTRACT FROM AUTHOR]

Gene-environment interactions (G × E) have attracted considerable research interest in the past owing to their scientific and public health implications, but powerful statistical methods are required to successfully track down G × E, particularly at a genome-wide level. Previously, a case-only (CO) design has been proposed as a means to identify G × E with greater efficiency than traditional case-control or cohort studies. However, as with genotype-phenotype association studies themselves, hidden population stratification (PS) can impact the validity of G × E studies using a CO design. Since this problem has been subject to little research to date, we used comprehensive simulation to systematically assess the type I error rate, power and effect size bias of CO studies of G × E in the presence of PS. Three types of PS were considered, namely genetic-only (PS), environment-only (PS), and joint genetic and environmental stratification (PS). Our results reveal that the type I error rate of an unadjusted Wald test, appropriate for the CO design, would be close to its nominal level (0.05 in our study) as long as PS involves only one interaction partner (i.e., either PS or PS). In contrast, if the study population is stratified with respect to both G and E (i.e., if there is PS), then the type I error rate is seriously inflated and estimates of the underlying G × E interaction are biased. Comparison of CO to a family-based case-parents design confirmed that the latter is more robust against PS, as expected. However, case-parent trios may be particularly unsuitable for G × E studies in view of the fact that they require genotype data from parents and that many diseases with an environmental component are likely to be of late onset. An alternative approach to adjusting for PS is principal component analysis (PCA), which has been widely used for this very purpose in past genome-wide association studies (GWAS). However, resolving genetic PS properly by PCA requires genetic data at the population level, the availability of which would conflict with the basic idea of the CO design. Therefore, we explored three modified Wald test statistics, inspired by the genomic control (GC) approach to GWAS, as an alternative means to allow for PS. The modified statistics were benchmarked against a stratified Wald test assuming known population affiliation, which should provide maximum power under PS. Our results confirm that GC is capable of successfully and efficiently correcting the PS-induced inflation of the type I error rate in CO studies of G × E. [ABSTRACT FROM AUTHOR]

This study reports the outcomes of childhood and adolescent eating-disordered behaviour on the development of body mass index (BMI) and psychological functioning in young adulthood in a population-based sample in Germany (the BELLA study). Information at baseline and follow-up was obtained through a telephone interview and mailed self-report questionnaires. At both measurement points, BMI, eating disorder symptoms (SCOFF questionnaire), and symptoms of depression and anxiety were assessed in the same cohort of 771 participants ( n = 420 females, n = 351 males). The age range at baseline was 11-17 years, and the age range at follow-up was 17-23 years. High scores for eating-disordered behaviour in childhood or adolescence significantly predicted eating-disordered behaviour in young adulthood (multiplicative effect estimate: 1.31; 95 % CI: 1.2-1.42, p < 0.0001), although there was a decline in prevalence (from 19.3 to 13.8 %, p = 0.002) and severity (mean decrease in SCOFF 0.07, 95 % CI: −0.01-0.14, p = 0.06). After accounting for potentially confounding variables at baseline (SES, probands' BMI, parental BMI, depressive symptoms), participants with more eating disorder symptoms at baseline had a higher risk of developing overweight (odds ratio (OR): 1.58; 95 % CI: 1.19-2.09, p = 0.001), obesity (OR = 1.67; 95 % CI: 1.03-2.66, p = 0.03), and depressive symptoms at follow-up (additive effect estimate: 0.45; 95 %CI: 0.19-0.7, p = 0.0006). Early symptoms of depression showed a significant relationship with extreme underweight in young adulthood (OR = 1.13; 95 %CI: 1.01-1.25, p = 0.02). The high stability of eating disorder symptoms and the significant association with overweight and worse mental health in adulthood underscore the need for early detection and intervention during childhood and adolescence. Youth with depression should be monitored for the development of restrictive eating disorders. [ABSTRACT FROM AUTHOR]

Body mass index (BMI) is one of the most important outcome predictors in patients with anorexia nervosa (AN). A low premorbid BMI percentile calculated by the patients recalled premorbid weight and the height at first admission has been found to predict the BMI at first inpatient admission. In this study, we sought to confirm this relationship. We additionally analyze the relationship between premorbid BMI percentile and BMI percentile at discharge from the first inpatient treatment and at 1-year follow-up or alternatively if applicable upon readmission within this time period. We included 161 female patients aged 11-18 years of the multisite ANDI-trial with a DSM-IV diagnosis of AN. We used a multivariate statistical model including the independent variables age, duration of illness, duration of treatment, BMI at admission and BMI percentile at discharge. The relationship between premorbid BMI percentile and BMI at admission was solidly confirmed. In addition to premorbid BMI percentile, BMI at admission and age were significant predictors of BMI percentile at discharge. BMI percentile at discharge significantly predicted BMI percentile at 1-year follow-up. An additional analysis that merely included variables available upon referral revealed that premorbid BMI percentile predicts the 1-year follow-up BMI percentile. Further studies are required to identify the underlying biological mechanisms and to address the respective treatment strategies for AN patients with a low or high premorbid BMI percentile. [ABSTRACT FROM AUTHOR]

Although there are many studies available investigating internalizing and externalizing behavior in childhood and adolescent manifestations of attention-deficit/hyperactivity disorder, there is limited information about their relevance in adults featuring persistence of the disease. We examined a large sample of 910 adults affected with attention-deficit/hyperactivity disorders (AADHD) for internalizing and externalizing behavior. Regarding correlates of internalizing behavior, AADHD probands showed significantly higher scores of the anxiety- and depression-related personality traits Neuroticism and Harm Avoidance, compared with reference values. The lifetime comorbidity of depressive disorders, anxiety disorders, and anxious or fearful Cluster C personality disorders (PDs) is elevated in AADHD patients compared with general population. Regarding correlates of externalizing behavior, patients affected with AADHD show significantly lower scores of Conscientiousness and significantly higher scores of Novelty Seeking than the published German reference values. Emotional, dramatic, or erratic Cluster B PDs were most frequent in AADHD. Internalizing and externalizing behavior notably affected psychosocial status to a similar extent. The frequency of both internalizing and externalizing behavior in AADHD might reflect an underlying emotional regulation disorder. [ABSTRACT FROM AUTHOR]

Body mass index (BMI) at admission is an important predictor of outcome in adolescent eating disorders. However, few studies have investigated BMI at admission, its changes in recent years, or modifying factors, such as duration of illness and age at onset in different geographical regions. Thus, this study aimed to investigate changes in BMI at admission over the past decade in one clinic, the differences in BMI between various treatment sites and the influence of duration of illness before admission and age at admission. Our sample consisted of 158 adolescent female patients with anorexia nervosa (AN) admitted between 2001 and 2009 to a major university hospital and 169 adolescent female patients recruited in a multicenter study between 2007 and 2010. We assessed the differences between departments in different regions of Germany in the multi-site sample. Changes over time in age-adjusted BMI and age at admission as well as modifying factors for age-adjusted BMI at admission, such as age at admission and duration of illness, were assessed in a representative local sample. There were no significant differences between departments in different regions of Germany. Over the course of the local study, there was a small but significant increase in the age-adjusted BMI score and absolute BMI at admission. In addition, there was a positive association between year of admission and age at admission. Older adolescents with AN had a lower age-adjusted BMI score and a longer duration of illness at the time of admission. The BMI at admission, which is one of the most important predictors of outcome in AN, has increased slightly during the past 10 years. Education strategies for parents and professionals should continue to be improved to further shorten the duration of illness before admission, especially for older adolescents. [ABSTRACT FROM AUTHOR]

While an interactive effect of genes with adverse life events is increasingly appreciated in current concepts of depression etiology, no data are presently available on interactions between genetic and environmental (G × E) factors with respect to personality and related disorders. The present study therefore aimed to detect main effects as well as interactions of serotonergic candidate genes (coding for the serotonin transporter, 5-HTT; the serotonin autoreceptor, HTR1A; and the enzyme which synthesizes serotonin in the brain, TPH2) with the burden of life events (#LE) in two independent samples consisting of 183 patients suffering from personality disorders and 123 patients suffering from adult attention deficit/hyperactivity disorder (aADHD). Simple analyses ignoring possible G × E interactions revealed no evidence for associations of either #LE or of the considered polymorphisms in 5-HTT and TPH2. Only the G allele of HTR1A rs6295 seemed to increase the risk of emotional-dramatic cluster B personality disorders ( p = 0.019, in the personality disorder sample) and to decrease the risk of anxious-fearful cluster C personality disorders ( p = 0.016, in the aADHD sample). We extended the initial simple model by taking a G × E interaction term into account, since this approach may better fit the data indicating that the effect of a gene is modified by stressful life events or, vice versa, that stressful life events only have an effect in the presence of a susceptibility genotype. By doing so, we observed nominal evidence for G × E effects as well as main effects of 5-HTT-LPR and the TPH2 SNP rs4570625 on the occurrence of personality disorders. Further replication studies, however, are necessary to validate the apparent complexity of G × E interactions in disorders of human personality. [ABSTRACT FROM AUTHOR]

Genetic and environmental risk factors and their interactions contribute to the development of complex diseases. In this review, we discuss methodological issues involved in investigating gene–environment (G × E) interactions in genetic–epidemiological studies of complex diseases and their potential relevance for clinical application. Although there are some important examples of interactions and applications, the widespread use of the knowledge about G × E interaction for targeted intervention or personalized treatment (pharmacogenetics) is still beyond current means. This is due to the fact that convincing evidence and high predictive or discriminative power are necessary conditions for usefulness in clinical practice. We attempt to clarify conceptual differences of the term ‘interaction’ in the statistical and biological sciences, since precise definitions are important for the interpretation of results. We argue that the investigation of G × E interactions is more rewarding for the detailed characterization of identified disease genes (ie at advanced stages of genetic research) and the stratified analysis of environmental effects by genotype or vice versa. Advantages and disadvantages of different epidemiological study designs are given and sample size requirements are exemplified. These issues as well as a critical appraisal of common methodological concerns are finally discussed.European Journal of Human Genetics (2008) 16, 1164–1172; doi:10.1038/ejhg.2008.106; published online 4 June 2008 [ABSTRACT FROM AUTHOR]

Copy number variants (CNVs) are pieces of genomic DNA of 1000 base pairs or longer which occur in a given genome at a different frequency than in a reference genome. Their importance as a source for phenotypic variability has been recognized only in the last couple of years. Chromosomal deletions can be seen as a special case of CNVs where stretches of DNA are missing in certain lines when compared to the reference genome of the mouse line C57BL/6, for example. Based upon more than 8 million single nucleotide polymorphisms (SNPs) in the fifteen inbred mouse lines which were determined in a whole genome chip based resequencing project by Perlegen Sciences, we detected 20 166 such long chromosomal deletions. They cover altogether between 4.4 million and 8.8 million base pairs, depending on the mouse line. Thus, their extent is comparable to that of SNPs. The chromosomal deletions were found by searching for clusters of missing values in the genotyping data by applying bioinformatics and biostatistical methods. In contrast to isolated missing values, clusters are likely the consequence of missing DNA probe rather than of a failed hybridization or deficient oligos. We analyzed these deletion sites in various ways. Twenty-two percent of these deletion sites overlap with exons; they could therefore affect a gene’s functioning. The corresponding genes seem to exist in alternative forms, a phenomenon that reminds of the alternative forms of mRNA generated during gene splicing. We furthermore detected statistically significant association between hundreds of deletion sites and fat weight at the age of eight weeks. [ABSTRACT FROM AUTHOR]

The prevalence and consequences of co-morbid axis-I and axis-II disorders as well as personality traits were examined in a large cohort of adult attention-deficit/hyperactivity disorder (AADHD) at a tertiary referral center. In- and outpatients referred for diagnostic assessment of AADHD were screened. 372 affected probands were examined by means of the Structured Clinical Interview of DSM-IV axis-I/II disorders, the Revised NEO Personality Inventory (NEO-PI-R), and the Tridimensional Personality Questionnaire (TPQ). Lifetime co-morbidity with mood disorders was 57.3%, with anxiety disorders 27.2%, and with substance use disorders 45.0%. The histrionic personality disorder (35.2%) was the most frequent personality disorder. AADHD patients exhibited significantly altered scores on most of the NEO-PI-R and TPQ personality dimensions. The extent of substance abuse and dependence, as well as the presence of antisocial personality disorder alone or the cumulative number of other specific personality disorders was associated with lower psychosocial status (p < .0001). In a cohort of patients with AADHD referred to a single tertiary center co-morbidity with axis-I/II disorders was remarkably prevalent. In AADHD co-morbid mood, anxiety, and personality disorders as well as substance abuse/dependence is likely to be predictive of poor outcome. [ABSTRACT FROM AUTHOR]