Exploring the potential association among sleep disturbances,cognitive impairments,and immune activation in 22q11.2 deletion syndrome

22q11.2 deletion syndrome (22q11.DS) is a neurogenetic disorder caused by a microdeletion in chromosome 22. Its phenotype includes high rates of psychiatric disorders, immune system abnormalities, and cognitive impairments. We assessed the quality of sleep in 22q11.2DS and its potential link to inflammatory markers and cognitive deficits. Thirty‐three 22q11.2DS individuals and 24 healthy controls were studied. Sleep parameters were assessed by the Pittsburgh sleep quality index (PSQI) questionnaire and correlated with serum cytokine levels and cognitive functioning, measured using the Penn computerized neurocognitive battery (CNB). The 22q11.2DS individuals had significantly worse sleep quality scores than the controls, unrelated to the psychiatric or physical comorbidities common to 22q11.2DS. Interleukin 6 levels were correlated with the overall score of the PSQI questionnaire for nonpsychotic 22q11.2DS participants only. Several domains of the CNB were associated with poorer sleep quality, suggesting that cognitive impairments in 22q11.2DS may be at least partially explained by poor sleep quality. Our findings confirm sleep impairments in individuals with 22q11.2DS, which might negatively affect their cognitive functioning, and corroborate a potential role of immunological pathways in the 22q11.2DS neuro‐phenotype.     

Neurocognitive Functioning in Patients with 22q11.2 Deletion Syndrome: A Meta-Analytic Review

The 22q11.2 deletion syndrome (22q11.2DS) is a known risk factor for development of schizophrenia and is characterized by a complex neuropsychological profile. To date, a quantitative meta-analysis examining cognitive functioning in 22q11.2DS has not been conducted. A systematic review of cross-sectional studies comparing neuropsychological performance of individuals with 22q11.2DS with age-matched healthy typically developing and sibling comparison subjects was carried out. Potential moderators were analyzed. Analyses included 43 articles (282 effects) that met inclusion criteria. Very large and heterogeneous effects were seen for global cognition (d = ? 1.21) and in specific neuropsychological domains (intellectual functioning, achievement, and executive function; d range = ? 0.51 to ? 2.43). Moderator analysis revealed a significant role for type of healthy comparison group used (typically developing or siblings), demographics (age, sex) and clinical factors (externalizing behavior). Results revealed significant differences between pediatric and adult samples, with isolated analysis within the pediatric sample yielding large effects in several neuropsychological domains (intellectual functioning, achievement, visual memory; d range = ? 0.56 to ? 2.50). Large cognitive deficits in intellectual functioning and specific neuropsychological variables in individuals with 22q11.2DS represent a robust finding, but these deficits are influenced by several factors, including type of comparison group utilized, age, sex, and clinical status. These findings highlight the clinical relevance of characterizing cognitive functioning in 22q11.2DS and the importance of considering demographic and clinical moderators in future analyses.     

Non‐pharmacological treatment of psychiatric disorders in individuals with 22q11.2 deletion syndrome; a systematic review

22q11.2 deletion syndrome (22q11.2DS) is associated with high rates of anxiety disorders, psychotic disorders, and other psychiatric conditions. In the general population, psychiatric disorders are treated with proven pharmacological and non‐pharmacological therapies, such as cognitive behavioral therapy (CBT). To begin to assess the feasibility and efficacy of non‐pharmacological therapies in 22q11.2DS, we performed a systematic search to identify literature on non‐pharmacological interventions for psychiatric disorders in individuals with 22q11.2DS. Of 1,240 individual publications up to mid‐2016 initially identified, 11 met inclusion criteria. There were five literature reviews, five publications reporting original research (two originating from a single study), and one publication not fitting either category that suggested adaptations to an intervention without providing scientific evidence. None of the original research involved direct study of the evidence‐based non‐pharmacological therapies available for psychiatric disorders. Rather, these four studies involved computer‐based or group interventions aimed at improving neuropsychological deficits that may be associated with psychiatric disorders. Although the sample sizes were relatively small (maximum 28 participants in the intervention group), these reports documented the promising feasibility of these interventions, and improvements in domains of neuropsychological functioning, including working memory, attention, and social cognition. The results of this review underline the need for research into the feasibility and efficacy of non‐pharmacological treatments of psychiatric disorders in individuals with 22q11.2DS to inform clinical care, using larger samples, and optimally, standard randomized, placebo‐controlled, clinical trials methodology.

     

Clinical phenotype of the recurrent 1q21.1 copy-number variant

PurposeTo characterize the clinical phenotype of the recurrent copy-number variation (CNV) at 1q21.1, we assessed the psychiatric and medical phenotypes of 1q21.1 deletion and duplication carriers ascertained through clinical genetic testing and family member cascade testing, with particular emphasis on dimensional assessment across multiple functional domains.MethodsNineteen individuals with 1q21.1 deletion, 19 individuals with the duplication, and 23 familial controls (noncarrier siblings and parents) spanning early childhood through adulthood were evaluated for psychiatric, neurologic, and other medical diagnoses, and their cognitive, adaptive, language, motor, and neurologic domains were also assessed. Twenty-eight individuals with 1q21.1 CNVs (15 deletion, 13 duplication) underwent structural magnetic resonance brain imaging.ResultsProbands with 1q21.1 CNVs presented with a range of psychiatric, neurologic, and medical disorders. Deletion and duplication carriers shared several features, including borderline cognitive functioning, impaired fine and gross motor functioning, articulation abnormalities, and hypotonia. Increased frequency of Autism Spectrum Disorder (ASD) diagnosis, increased ASD symptom severity, and increased prevalence of macrocephaly were observed in the duplication relative to deletion carriers, whereas reciprocally increased prevalence of microcephaly was observed in the deletion carriers.ConclusionsIndividuals with 1q21.1 deletions or duplications exhibit consistent deficits on motor and cognitive functioning and abnormalities in head circumference.     

Schizophrenic-like neurocognitive deficits in children and adolescents with 22q11 deletion syndrome.

22q11.2 Deletion Syndrome (22q11DS) is the most common genetic microdeletion syndrome affecting humans. The syndrome is associated with general cognitive impairments and specific deficits in visual-spatial ability, non-verbal reasoning, and planning skills. 22q11DS is also associated with behavioral and psychiatric abnormalities, including a markedly elevated risk for schizophrenia. Research findings indicate that people with schizophrenia, as well as those identified as schizoptypic, show specific cognitive deficits in the areas of sustained attention, executive functioning, and verbal working memory. The present study examined such schizophrenic-like cognitive deficits in children and adolescents with 22q11DS (n = 26) and controls (n = 25) using a cross-sectional design. As hypothesized, 22q11DS participants exhibited deficits in intelligence, achievement, sustained attention, executive functioning, and verbal working memory compared to controls. Furthermore, deficits in attention and executive functioning were more pronounced in the 22q11DS sample relative to general cognitive impairment. These findings suggest that the same pattern of neuropsychological impairment seen in patients with schizophrenia is present in non-psychotic children identified as at-risk for the development of schizophrenia based on a known genetic risk marker.     

The role of COMT and plasma proline in the variable penetrance of autistic spectrum symptoms in 22q11.2 deletion syndrome

This paper examines how COMT¹⁵⁸ genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer‐based test‐paradigms. Associations with COMT¹⁵⁸ genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMT^MET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMT^MET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT¹⁵⁸ genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants.     

Neurodevelopmental and other psychiatric disorders in 22q11.2 deletion syndrome from childhood to adult age: Prospective longitudinal study of 100 individuals

The 22q11.2 deletion syndrome (22q11.2DS), affects physical as well as cognitive and emotional functioning with increased risk for psychiatric and behavioral problems. This longitudinal study of 79 individuals (18–50 years) with 22q11.2DS investigated neurodevelopmental (NDD) and psychiatric disorders in adulthood, evaluated the stability of childhood diagnoses over time, and examined associations between clinical characteristics in childhood/adolescence and diagnostic outcome in adult age. Examination using validated instruments for cognitive, psychiatric, and global functional problems in the context of an in-depth clinical evaluation found adult age stability of NDD diagnoses made in childhood, however, rates increased at follow-up. Rates of anxiety, mood, and psychotic disorders were high, with a majority meeting diagnostic criteria for one or more psychiatric disorder. The rate of psychotic disorders was much lower compared to many other studies. Variability in functioning at follow-up was primarily associated with intellectual ability at T1. The findings obtained highlight the increased risk of NDD and psychiatric problems and of cognitive impairment and reduced levels of global functioning over time. Results emphasize the importance of clinical follow-up to enable appropriate support for the promotion of optimal health along with a need for future research on effective interventions and treatment strategies.     

The clinical presentation of attention deficit‐hyperactivity disorder (ADHD) in children with 22q11.2 deletion syndrome

Background: Although attention deficit‐hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder in children with 22q11.2DS, it remains unclear whether its clinical presentation is similar to that in children with idiopathic ADHD. The aim of this study is to compare the ADHD phenotype in children with and without 22q11.2DS by examining ADHD symptom scores, patterns of psychiatric comorbidity, IQ and gender distribution. Methods: Forty‐four children with 22q11.2DS and ADHD (mean age = 9.6), 600 clinic children (mean age = 10.8) and 77 children with ADHD from a population cohort (mean age = 10.8) participated in the study. Psychopathology was assessed using parent‐report research diagnostic instruments. Results: There was a higher proportion of females in the 22q11.2DS ADHD sample in relation to the clinical sample (χ² = 18.2, P < 0.001). The 22q11.2DS group showed a higher rate of ADHD inattentive subtype (χ² = 114.76, P < 0.001), and fewer hyperactive‐impulsive symptoms compared to the clinical group (z = 8.43, P < 0.001). The 22q11.2DS ADHD group parents reported fewer oppositional defiant disorder/conduct disorder symptoms (z = 6.33, P < 0.001) and a higher rate of generalized anxiety disorder (χ² = 4.56, P = 0.03) in relation to the clinical group. Two percent of the 22q11.2 DS ADHD sample had received ADHD treatment. The results were similar when the 22q11.2 ADHD group was compared to the population cohort ADHD group. Conclusions: The clinical presentation of ADHD and patterns of co‐morbidity in 22q11.2DS is different from that in idiopathic ADHD. This could lead to clinical under‐recognition of ADHD in this group. Examining psychopathology in 22q11.2DS can provide insights into the genetic origins of psychiatric problems with implications beyond the 22q11.2DS population. © 2015 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.     

Fetal growth and gestational factors as predictors of schizophrenia in 22q11.2 deletion syndrome

PurposeSchizophrenia occurs in 20–25% of adults with 22q11.2 deletion syndrome (22q11.2DS). General population studies of schizophrenia report associations with perinatal complications, although effect sizes are generally low. We aimed to determine whether such factors are associated with expression of schizophrenia in individuals with 22q11.2DS.MethodsWe investigated the relationship of small for gestational age (SGA) birth weight (<3rd percentile for sex and gestational age) and prematurity (<37 weeks gestation) to expression of schizophrenia in a well-characterized cohort of 123 adults with 22q11.2DS. Outcome measures included adjusted odds ratios and positive and negative predictive values (PPV and NPV) for schizophrenia.ResultsSGA birth weight (OR = 3.52, 95% CI = 1.34–9.22) and prematurity (OR = 5.38, 95% CI = 1.63–17.75), but not maternal factors, were significant risk factors for schizophrenia in 22q11.2DS. Being born SGA or premature resulted in a PPV of 46% for schizophrenia; NPV in the absence of both features was 83%. Post hoc analyses suggested these perinatal complications were also associated with factors indicative of increased severity of schizophrenia.ConclusionIn 22q11.2DS, fetal growth and gestation may have a clinically significant impact on future risk for schizophrenia. These data advance our understanding of determinants of disease-specific expression in 22q11.2DS, with implications for other genomic disorders.     

Discussing the psychiatric manifestations of 22q11.2 deletion syndrome: an exploration of clinical practice among medical geneticists

PurposeThe aim of this study was to determine the frequency with which medical geneticists discuss the psychiatric manifestations of 22q11.2 deletion syndrome (22q11DS) with families in relation to the frequency with which they discuss the other manifestations of the syndromes and to explore relationships between discussion of these features and stigma toward psychiatric disorders.MethodsWe surveyed medical geneticists in the United States and Canada regarding the frequency with which they discuss various features of 22q11DS with families in the context of four clinical scenarios in which only the age of the patient at diagnosis differed. Respondents also completed a 20-item validated psychometric measure of stigma toward psychiatric disorders.Results308 of 546 medical geneticists completed the survey (56% response rate). Overall, psychiatric disorders were discussed significantly less often than other features of 22q11DS (P < 0.0001) but were discussed significantly more often when the patient was 13 years or older (P < 0.0001) than when the patient was younger. Geneticists who discussed psychiatric disorders the least had significantly higher levels of stigma toward psychiatric disorders (P = 0.007).ConclusionPsychiatric manifestations of 22q11DS are less often discussed with families during childhood. Education for physicians to help reduce stigma toward psychiatric disorders (which may impede discussion of psychiatric disorders) may warrant exploration in this population.Genet Med15 9, 713–720.     

Functional outcomes of adults with 22q11.2 deletion syndrome

PurposeThe 22q11.2 deletion syndrome is a common multisystem genomic disorder with congenital and later-onset manifestations, including congenital heart disease, intellectual disability, and psychiatric illness, that may affect long-term functioning. There are limited data on adult functioning in 22q11.2 deletion syndrome.MethodsWe used the Vineland Adaptive Behavior Scales to assess functioning in 100 adults with 22q11.2 deletion syndrome (n = 46 male; mean age = 28.8 (standard deviation = 9.7) years) where intellect ranged from average to borderline (n = 57) to mild intellectual disability (n = 43).ResultsMore than 75% of the subjects scored in the functional deficit range. Although personal, vocational, and financial demographics confirmed widespread functional impairment, daily living skills and employment were relative strengths. Intelligence quotient was a significant predictor (P < 0.001) of overall and domain-specific adaptive functioning skills. A diagnosis of schizophrenia was a significant predictor (P < 0.05) of overall adaptive functioning, daily living skills, and socialization scores. Notably, congenital heart disease, history of mood/anxiety disorders, sex, and age were not significant predictors of functioning.ConclusionDespite functional impairment in adulthood that is primarily mediated by cognitive and psychiatric phenotypes, relative strengths in activities of daily living and employment have important implications for services and long-term planning. These results may help to inform expectations about outcomes for patients with 22q11.2 deletion syndrome.Genet Med 2012:14(10):836–843     

Presenting symptoms in adults with the 22q11 deletion syndrome

A definitive molecular diagnosis of 22q11 Deletion Syndrome (22q11DS) even if occurring later in life, has important genetic, medical and emotional impact on the patients and their families. The aim of this study is to describe presenting symptoms and age at diagnosis in an adult 22q11DS population.A retrospective study was performed on 65 individuals diagnosed with 22q11DS at adult age. Data were collected on adults referred to the genetic clinic or actively recruited through systematic diagnostic examination in both institutions and a psychiatric unit for intellectually disabled. Presenting symptoms were categorized into seven groups: familial occurrence, intellectual disability, cardiac anomalies, palatal anomalies, facial dysmorphic features, psychiatric problems and ‘other’ (comprising all other features associated with 22q11DS). Age at diagnosis was defined as the age at which the 22q11.2 deletion was detected by fluorescence in situ hybridization or comparative genomic hybridization. Ascertainment subgroups were different in presenting symptoms and age at diagnosis. Adults were referred to the genetic clinic mainly because of familial occurrence, cardiac defects and psychiatric disorders whereas adults diagnosed in institutions for intellectually disabled presented mainly with moderate to severe intellectual disability and psychotic disorders. Adults diagnosed at the psychiatric unit for intellectually disabled had a variety of psychiatric disorders but none of them had additional physical features.This emphasizes the need to stay alert for presenting symptoms such as conotruncal heart defects or moderate to severe intellectual disability in combination with a history of psychiatric disorders, even in the absence of obvious physical features.     

Cardiac function in adolescents and young adults with 22q11.2 deletion syndrome without congenital heart disease

BackgroundDiagnosis and treatment of 22q11.2 deletion syndrome (22q11.2DS) have led to improved life expectancy and achievement of adulthood. Limited data on long-term outcomes reported an increased risk of premature death for cardiovascular causes, even without congenital heart disease (CHD). The aim of this study was to assess the cardiac function in adolescents and young adults with 22q11.2DS without CHDs.MethodsA total of 32 patients (20M, 12F; mean age 26.00 ± 8.08 years) and a healthy control group underwent transthoracic echocardiography, including Tissue Doppler Imaging (TDI) and 2-dimensional Speckle Tracking Echocardiography (2D-STE).ResultsCompared to controls, 22q11.2DS patients showed a significant increase of the left ventricle (LV) diastolic and systolic diameters (p = 0.029 and p = 0.035 respectively), interventricular septum thickness (p = 0.005), LV mass index (p < 0.001) and aortic root size (p < 0.001). 2D-STE analysis revealed a significant reduction of LV global longitudinal strain (p < 0.001) in 22q11.2DS than controls. Moreover, several LV diastolic parameters were significantly different between groups.ConclusionsOur results suggest that an echocardiographic follow-up in 22q11.2DS patients without CHDs can help to identify subclinical impairment of the LV and evaluate a potential progression of aortic root dilation over time, improving outcomes, reducing long-term complications and allowing for a better prognosis.     

Medical,welfare, and educational challenges and psychological distress in parents caring for an individual with 22q11.2 deletion syndrome: A cross-sectional survey in Japan

Parents of children with 22q11.2 deletion syndrome (22q11DS) experience distress not only due to multimorbidity in the patients, but also due to professionals' lack of understanding about 22q11DS and insufficient support systems. This study investigated relationships between medical, welfare, and educational challenges and parental psychological distress. A cross-sectional survey was conducted on primary caregivers of children with 22q11DS. Participants included 125 parents (114 mothers, 91.2%; average age = 44.3 years) who reported their challenges, psychological distress, and child's comorbidities of 22q11DS. Results showed that the difficulty in going to multiple medical institutions (β = 0.181, p < 0.05) and lack of understanding by welfare staff and insufficient welfare support systems for 22q11DS (β = 0.220–0.316, all p < 0.05) were associated with parental psychological distress, even after adjusting for child's comorbidities. In the subsample of parents whose child attended an educational institution, inadequate management in classroom and mismatch between service and users in educational settings were associated with psychological distress (β = 0.222–0.296, all p < 0.05). This study reveals the importance of assessing not only severity of comorbidities in 22q11DS, but also the medical, welfare, and educational challenges for parental mental health.     

Obesity in adults with 22q11.2 deletion syndrome

PurposeTo characterize the prevalence of and contributing factors to adult obesity in the most common recurrent copy-number variation (CNV), 22q11.2 deletion, given that other rare CNVs are known to have obesity phenotypes.MethodsIn 207 adults with 22q11.2 deletion syndrome (22q11.2DS), we used available height and weight measurements to calculate body mass index (BMI) and recorded associated factors that could play a role in obesity. We used the maximum BMI per subject and logistic regression to test a model predicting obesity class.ResultsThe prevalence of obesity (BMI ≥30) in 22q11.2DS (n = 90, 43.5%; at median age of 26.7 years) was significantly greater than for Canadian norms (odds ratio (OR) 2.30, 95% confidence interval (CI) = 1.74–3.02, P < 0.0001), even after excluding individuals with a history of antipsychotic use. The regression model was significant (P < 0.0001). Psychotropic medication use and age, but not sex or presence of intellectual disability, were associated with higher obesity level. Ten (4.8%) individuals were diagnosed with type 2 diabetes at a median age of 39.5 years; the prevalence was higher in those with obesity (P < 0.01).ConclusionThe results suggest that adult obesity is related to the 22q11.2 deletion. The findings expand the potential genetic causes of obesity and have important implications for management of 22q11.2DS.     

Practical guidelines for managing adults with 22q11.2 deletion syndrome

22q11.2 Deletion syndrome (22q11.2DS) is the most common microdeletion syndrome in humans, estimated to affect up to 1 in 2,000 live births. Major features of this multisystem condition include congenital anomalies, developmental delay, and an array of early- and later-onset medical and psychiatric disorders. Advances in pediatric care ensure a growing population of adults with 22q11.2DS. Informed by an international panel of multidisciplinary experts and a comprehensive review of the existing literature concerning adults, we present the first set of guidelines focused on managing the neuropsychiatric, endocrine, cardiovascular, reproductive, psychosocial, genetic counseling, and other issues that are the focus of attention in adults with 22q11.2DS. We propose practical strategies for the recognition, evaluation, surveillance, and management of the associated morbidities.Genet Med17 8, 599–609.     

Increased Levels of Interferon‐Inducible Protein 10 (IP‐10) in 22q11.2 Deletion Syndrome

The 22q11.2 deletion syndrome (22q11.2 DS), also known as DiGeorge syndrome, is a genetic disorder with an estimated incidence of 1:4000 births. These patients may suffer from affection of many organ systems with cardiac malformations, thymic hypoplasia or aplasia, hypoparathyroidism, palate anomalies and psychiatric disorders being the most frequent. The incidence of autoimmune diseases is increased in older patients. The aim of the present study was to examine a cytokine profile in patients with 22q11.2 DS by measuring a broad spectrum of serum cytokines. Patients with a proven deletion of chromosome 22q11.2 (n = 55) and healthy individuals (n = 54) recruited from an age‐ and sex‐comparable group were included in the study. Serum levels of 27 cytokines, including chemokines and growth factors, were analysed using multiplex technology. Interferon‐inducible protein 10 (IP‐10) was also measured by ELISA to confirm the multiplex results. The 22q11.2 DS patients had distinctly and significantly raised levels of pro‐inflammatory and angiostatic chemokine IP‐10 (P < 0.001) compared to controls. The patients with congenital heart defects (n = 31) had significantly (P = 0.018) raised serum levels of IP‐10 compared to patients born without heart defects (n = 24). The other cytokines investigated were either not detectable or did not differ between patients and controls.     

All-cause mortality and survival in adults with 22q11.2 deletion syndrome

PurposeGiven limited data available on long-term outcomes in 22q11.2 deletion syndrome (22q11.2DS), we investigated mortality risk in adults with this microdeletion syndrome.MethodsWe studied 309 well-characterized adults (age ≥17 years) with 22q11.2DS and their 1014 unaffected parents and siblings, using a prospective case–control design. We used Cox proportional hazards regression modeling and Kaplan–Meier curves to investigate effects of the 22q11.2 deletion and its associated features on all-cause mortality and survival.ResultsThe 22q11.2 deletion (hazard ratio [HR] 8.86, 95% CI 2.87–27.37) and major congenital heart disease (CHD; HR 5.03, 95% CI 2.27–11.17), but not intellectual disability or psychotic illness, were significant independent predictors of mortality for adults with 22q11.2DS compared with their siblings. Amongst those with 22q11.2DS, there were 31 deaths that occurred at a median age of 46.4 (range 18.1–68.6) years; a substantial minority had outlived both parents. Probability of survival to age 45 years was approximately 72% for those with major CHD, and 95% for those with no major CHD (p < 0.0001).ConclusionFor adults with 22q11.2DS, the 22q11.2 deletion and more severe forms of CHD both contribute to a lower life expectancy than family-based expectations. The results have implications for genetic counseling and anticipatory care.     

Riluzole effectively treats psychotic symptoms and improves cognition in 22q11.2 deletion syndrome: A clinical case

22q11.2 deletion syndrome (22q11DS) is a genetic disorder caused by a hemizygous microdeletion on the long arm of chromosome 22 and is associated with a high risk for psychosis and cognitive impairment. One of the genes located in the deleted region of 22q11DS is Proline Dehydrogenase (PRODH) which is important for conversion of proline to glutamate. Glutamate is the primary excitatory neurotransmitter and is involved in the pathophysiology of psychosis as well as in cognition. Excessive concentrations are toxic. Possibly, neuroprotective drugs modulating glutamatergic neurotransmission could be effective in treating psychotic symptoms and cognitive enhancement in patients with 22q11DS. Riluzole is a potent anti-glutamatergic drug that reduces glutamatergic neurotransmission. Here we report acute (single dose) and long-term effects of riluzole on glutamate and GABA levels in the anterior cingulate cortex (ACC) and striatum (measured with magnetic resonance spectroscopy, 1H-MRS) as well as on psychotic symptoms and cognitive functioning in a medication-free 23-year old woman with 22q11DS. Patient presented with frequent auditory and visual hallucinations and mild paranoid ideas. The ¹H-MRS measurements showed that after a single dose riluzole (50 mg), glutamate in the ACC and striatum was reduced whereas striatal GABA increased compared to baseline. Strikingly, hallucinations and paranoia disappeared. Therefore, riluzole treatment was initiated and patient was followed up after 18 months of treatment. At follow-up, patient reported no hallucinations or paranoia and several cognitive functions were improved. Furthermore, glutamate concentrations in the ACC and striatum decreased whereas GABA concentrations increased in the striatum but decreased in the ACC. These results suggests that riluzole may be an effective treatment option for psychotic symptoms and cognitive enhancement in 22q11DS. Results warrant replication in a bigger sample.     

Pathogenic variants in CDC45 on the remaining allele in patients with a chromosome 22q11.2 deletion result in a novel autosomal recessive condition

PurposeThe 22q11.2 deletion syndrome (22q11.2DS) is the most common microdeletion in humans, with highly variable phenotypic expression. Whereas congenital heart defects, palatal anomalies, immunodeficiency, hypoparathyroidism, and neuropsychiatric conditions are observed in over 50% of patients with 22q11DS, a subset of patients present with additional “atypical” findings such as craniosynostosis and anorectal malformations. Recently, pathogenic variants in the CDC45 (Cell Division Cycle protein 45) gene, located within the LCR22A–LCR22B region of chromosome 22q11.2, were noted to be involved in the pathogenesis of craniosynostosis.MethodsWe performed next-generation sequencing on DNA from 15 patients with 22q11.2DS and atypical phenotypic features such as craniosynostosis, short stature, skeletal differences, and anorectal malformations.ResultsWe identified four novel rare nonsynonymous variants in CDC45 in 5/15 patients with 22q11.2DS and craniosynostosis and/or other atypical findings.ConclusionThis study supports CDC45 as a causative gene in craniosynostosis, as well as a number of other anomalies. We suggest that this association results in a condition independent of Meier–Gorlin syndrome, perhaps representing a novel condition and/or a cause of features associated with Baller–Gerold syndrome. In addition, this work confirms that the phenotypic variability observed in a subset of patients with 22q11.2DS is due to pathogenic variants on the nondeleted chromosome.