Publications by authors named "Federico Sicca"

42 Publications

Sleep EEG microstructure in children and adolescents with attention deficit hyperactivity disorder: a systematic review and meta-analysis.

Sleep 2021 Jan 11. Epub 2021 Jan 11.

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy.

Attention deficit hyperactivity disorder (ADHD) is commonly associated with sleep problems, possibly due to shared pathophysiology. Microstructural sleep electroencephalographic (EEG) alterations may likely represent markers of disordered cortical maturation in ADHD, although literature data are still conflicting, deserving further assessment. After having systematically reviewed the literature, we included 11 studies from 598 abstracts, and assessed 23 parameters of cyclic alternating pattern (CAP), four parameters of sleep EEG power and one parameter of sleep graphoelements through 29 meta-analyses and, when possible, univariate meta-regressions. Slow wave activity (SWA) in ADHD was significantly higher in early childhood and lower in late childhood/adolescence compared to controls, with an inversion point at 10 years. Total CAP rate and CAP A1 index in non-rapid eye movement (NREM) stage 2 sleep, and CAP A1 rate in NREM sleep were significantly lower in ADHD patients than controls. SWA and CAP A1 changes are therefore possible markers of altered cortical maturation in ADHD, consistently with the neuropsychological deficits characterizing the disorder, likely fostering earlier detection of at-risk/milder conditions, and more tailored therapeutic interventions.
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http://dx.doi.org/10.1093/sleep/zsab006DOI Listing
January 2021

Psychopathological features in referred adolescents with psychogenic nonepileptic seizures with or without epilepsy.

Epilepsy Behav 2020 11 7;112:107431. Epub 2020 Sep 7.

IRCCS Stella Maris, Scientific Institute of Child Neurology and Psychiatry, Calambrone, Pisa, Italy.

Psychogenic nonepileptic seizures (PNES) are episodic manifestations that mimic epileptic seizures (ES) although not associated with electroencephalogram (EEG) abnormalities. Psychogenic nonepileptic seizures and ES, however, can often cooccur. Emotional distress in adolescents can trigger PNES, but the psychopathological and personality features are still unknown. The aim of this study was to explore psychopathological features in a sample of referred youth with PNES, with or without ES, compared with a control group with ES. Thirty-four patients aged 12 to 21 years, 19 females and 15 males, were included in the study, 15 patients with PNES, 7 with PNES and ES, and 12 with ES. The three groups were compared according to psychiatric categorical diagnoses, psychopathological dimensions, life stressors, and personality traits, including alexithymia, interpersonal reactivity, and resilience, all assessed with structured measures. Patients with PNES, with or without ES, were more severely impaired, had a higher incidence of mood disorders, more frequent lifetime traumatic experiences, and lower resilience. All the three groups presented alexythimic traits and emotional dysregulation. Major limitations are the small sample size and the lack of a control group of healthy subjects. Disentagling psychopathological characteristics in PNES can help clinicians to focus diagnostic approaches and therapeutic interventions.
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http://dx.doi.org/10.1016/j.yebeh.2020.107431DOI Listing
November 2020

Safe and sound: Meta-analyzing the Mozart effect on epilepsy.

Clin Neurophysiol 2020 Jul 30;131(7):1610-1620. Epub 2020 Apr 30.

EPILAB - Epilepsy and Clinical Neurophysiology Laboratory, Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy. Electronic address:

Objective: The use of music-based neuro-stimulation for treating seizures and interictal epileptiform discharges (IED) (the so-called "Mozart effect") remains a controversial issue. We have conducted an updated meta-analysis in order to systematically review literature evidence and provide further insights about the role of the Mozart effect in epilepsy.

Methods: Following the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) guidelines, we searched three bibliographic databases from their date of inception to January 2020. Nine meta-analyses were performed according to both music stimulation protocols and outcome measures. We applied the Cochrane Q-test and the I-index for heterogeneity evaluation, and either fixed-effect or random-effect models to compute mean differences and pool data.

Results: Of 147 abstracts, 12 studies were included and grouped according to stimulation protocols and outcome measures. The nine meta-analyses showed significant reductions in seizures and IED frequencies after long-term music treatment, and in IED frequency during and after a single music stimulus.

Conclusions: Music-based neurostimulation may improve the clinical outcome of individuals with epilepsy, by reducing the frequency of seizures and IED. Further and stronger evidence will allow defining its potential in the different forms of epilepsy, and the most effective stimulation protocols.

Significance: Music therapy should be considered as a complementary, non-invasive approach for treating epilepsy and epileptiform discharges.
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http://dx.doi.org/10.1016/j.clinph.2020.03.039DOI Listing
July 2020

Evolution of Epileptiform Activity in Zebrafish by Statistical-Based Integration of Electrophysiology and 2-Photon Ca Imaging.

Cells 2020 03 21;9(3). Epub 2020 Mar 21.

Molecular Medicine, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56028 Pisa, Italy.

The study of sources and spatiotemporal evolution of ictal bursts is critical for the mechanistic understanding of epilepsy and for the validation of anti-epileptic drugs. Zebrafish is a powerful vertebrate model representing an excellent compromise between system complexity and experimental accessibility. We performed the quantitative evaluation of the spatial recruitment of neuronal populations during physiological and pathological activity by combining local field potential (LFP) recordings with simultaneous 2-photon Ca imaging. We developed a method to extract and quantify electrophysiological transients coupled with Ca events and we applied this tool to analyze two different epilepsy models and to assess the efficacy of the anti-epileptic drug valproate. Finally, by cross correlating the imaging data with the LFP, we demonstrated that the cerebellum is the main source of epileptiform transients. We have also shown that each transient was preceded by the activation of a sparse subset of neurons mostly located in the optic tectum.
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http://dx.doi.org/10.3390/cells9030769DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140665PMC
March 2020

Expanding the clinical and genetic heterogeneity of SPAX5.

Ann Clin Transl Neurol 2020 04 1;7(4):595-601. Epub 2020 Apr 1.

IRCCS Fondazione Stella Maris, Calambrone, Pisa, Italy.

Mutations in the ATPase family 3-like gene (AFG3L2) have been linked to autosomal-dominant spinocerebellar ataxia type 28 and autosomal recessive spastic ataxia-neuropathy syndrome. Here, we describe the case of a child carrying bi-allelic mutations in AFG3L2 and presenting with ictal paroxysmal episodes associated with neuroimaging suggestive of basal ganglia involvement. Studies in skin fibroblasts showed a significant reduction of AFG3L2 expression. The relatively mild clinical presentation and the benign course, in spite of severe neuroimaging features, distinguish this case from data reported in the literature, and therefore expand the spectrum of neurological and neuroradiological features associated with AFG3L2 mutations.
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http://dx.doi.org/10.1002/acn3.51024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7187698PMC
April 2020

Loss of ap4s1 in zebrafish leads to neurodevelopmental defects resembling spastic paraplegia 52.

Ann Clin Transl Neurol 2020 04 25;7(4):584-589. Epub 2020 Mar 25.

Department of Molecular Medicine, IRCCS Stella Maris Foundation, Pisa, Italy.

Autosomal recessive spastic paraplegia 52 is caused by biallelic mutations in AP4S1 which encodes a subunit of the adaptor protein complex 4 (AP-4). Using next-generation sequencing, we identified three novel unrelated SPG52 patients from a cohort of patients with cerebral palsy. The discovered variants in AP4S1 lead to reduced AP-4 complex formation in patient-derived fibroblasts. To further understand the role of AP4S1 in neuronal development and homeostasis, we engineered the first zebrafish model of AP-4 deficiency using morpholino-mediated knockdown of ap4s1. In this model, we discovered several phenotypes mimicking SPG52, including altered CNS development, locomotor deficits, and abnormal neuronal excitability.
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http://dx.doi.org/10.1002/acn3.51018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7187712PMC
April 2020

Mitochondrial epilepsy: a cross-sectional nationwide Italian survey.

Neurogenetics 2020 04 3;21(2):87-96. Epub 2020 Jan 3.

IRCCS Fondazione Stella Maris, Pisa, Italy.

Many aspects of epilepsy in mitochondrial disorders (MDs) need to be further clarified. To this aim, we explored retrospectively a cohort of individuals with MDs querying the "Nationwide Italian Collaborative Network of Mitochondrial Diseases" (NICNMD) database (1467 patients included since 2010 to December 2016). We collected information on age at epilepsy onset, seizure type and frequency, genetic findings, and antiepileptic drugs (AEDs). At the time of our survey, 147/1467 (10%) patients in the NICNMD database had epilepsy. Complete information was available only for 98 patients, 52 males and 46 females, aged 5-92 years (mean age 40.4 ± 18.4; 14/98 children/teenagers and 84 adults). Epilepsy was the presenting feature of MD in 46/98 (47%) individuals, with onset at a median age of 19 years (range, 0.2-68; < 3 years in 14/97 (14%), 3-19 years in 36/97 (37%), > 19 years in 47/97 (49%)). Moreover, 91/98 patients (93%) displayed multiple seizures, with daily or weekly frequency in 25/91 (28%). Interictal EEG was abnormal in 70/78 (90%) patients, displaying abnormal background (47/70; 67%) and/or interictal paroxysms (53/70; 76%). Eighty of 90 patients (89%) displayed a 50-100% reduction of seizures on AEDs; levetiracetam was the most commonly used. Forty-one patients (42%) carried the m.3243A>G mutation, 16 (16%) the m.8344A>G, and 9 (9%) nuclear DNA (nDNA) mutations. Individuals with early-onset seizures mainly carried nDNA mutations and had a more severe epilepsy phenotype, higher seizure frequency, and disorganized background EEG activity. A better definition of epilepsy in MDs may foster the diagnostic workup, management, and treatment of affected patients, and allow more homogeneous patient stratification.
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http://dx.doi.org/10.1007/s10048-019-00601-5DOI Listing
April 2020

Customized multigene panels in epilepsy: the best things come in small packages.

Neurogenetics 2020 01 13;21(1):1-18. Epub 2019 Dec 13.

Molecular Medicine and Neurogenetics, Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Via dei Giacinti 2, 56028, Pisa, Italy.

Over the past 10 years, the increasingly important role played by next-generation sequencing panels in the genetic diagnosis of epilepsy has led to a growing list of gene variants and a plethora of new scientific data. To date, however, there is still no consensus on what constitutes the "ideal panel design," or on the most rational criteria for selecting the best candidates for gene-panel analysis, even though both might optimize the cost-benefit ratio and the diagnostic efficiency of customized gene panels. Even though more and more laboratories are adopting whole-exome sequencing as a first-tier diagnostic approach, interpreting, "in silico," a set of epilepsy-related genes remains difficult. In the light of these considerations, we performed a systematic review of the targeted gene panels for epilepsy already reported in the available scientific literature, with a view to identifying the best criteria for selecting patients for gene-panel analysis, and the best way to design an "ideal," gold-standard panel that includes all genes with an established role in epilepsy pathogenesis, as well as those that might help to guide decisions regarding specific medical interventions and treatments. Our analyses suggest that the usefulness and diagnostic power of customized gene panels for epilepsy may be greatest when these panels are confined to rationally selected, relatively small, pools of genes, and applied in more carefully selected epilepsy patients (those with complex forms of epilepsy). A panel containing 64 genes, which includes the 45 genes harboring a significant number of pathogenic variants identified in previous literature, the 32 clinically actionable genes, and the 21 ILAE (International League Against Epilepsy) recommended genes, may represent an "ideal" core set likely able to provide the highest diagnostic efficiency and cost-effectiveness and facilitate gene prioritization when testing patients with whole-exome/whole-genome sequencing.
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http://dx.doi.org/10.1007/s10048-019-00598-xDOI Listing
January 2020

Electrophysiological features of sleep in children with Kir4.1 channel mutations and Autism-Epilepsy phenotype: a preliminary study.

Sleep 2020 Apr;43(4)

SONNOLab, Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, Italy.

Study Objectives: Recently, a role for gain-of-function (GoF) mutations of the astrocytic potassium channel Kir4.1 (KCNJ10 gene) has been proposed in subjects with Autism-Epilepsy phenotype (AEP). Epilepsy and autism spectrum disorder (ASD) are common and complexly related to sleep disorders. We tested whether well characterized mutations in KCNJ10 could result in specific sleep electrophysiological features, paving the way to the discovery of a potentially relevant biomarker for Kir4.1-related disorders.

Methods: For this case-control study, we recruited seven children with ASD either comorbid or not with epilepsy and/or EEG paroxysmal abnormalities (AEP) carrying GoF mutations of KCNJ10 and seven children with similar phenotypes but wild-type for the same gene, comparing period-amplitude features of slow waves detected by fronto-central bipolar EEG derivations (F3-C3, F4-C4, and Fz-Cz) during daytime naps.

Results: Children with Kir4.1 mutations displayed longer slow waves periods than controls, in Fz-Cz (mean period = 112,617 ms ± SE = 0.465 in mutated versus mean period = 105,249 ms ± SE = 0.375 in controls, p < 0.001). An analog result was found in F3-C3 (mean period = 125,706 ms ± SE = 0.397 in mutated versus mean period = 120,872 ms ± SE = 0.472 in controls, p < 0.001) and F4-C4 (mean period = 127,914 ms ± SE = 0.557 in mutated versus mean period = 118,174 ms ± SE = 0.442 in controls, p < 0.001).

Conclusion: This preliminary finding suggests that period-amplitude slow wave features are modified in subjects carrying Kir4.1 GoF mutations. Potential clinical applications of this finding are discussed.
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http://dx.doi.org/10.1093/sleep/zsz255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7157183PMC
April 2020

Clinical and electroencephalographic correlates of psychiatric features in children with frontal lobe epilepsy.

Epilepsy Behav 2019 03 4;92:283-289. Epub 2019 Feb 4.

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy. Electronic address:

Background And Objective: Frontal lobe epilepsy (FLE) is often associated with psychiatric features, although the factors predisposing to the concurrence of these conditions have yet to be determined, especially in younger children. We aimed at defining possible clinical and electroencephalography (EEG) features that may enhance the psychiatric risk in pediatric FLE.

Method: We performed a structured psychiatric assessment of 59 children with FLE, using both categorical and dimensional approaches, correlated psychopathology with epilepsy data, and cognitive development.

Results: About 1/3 of patients with FLE displayed intellectual disability (ID), and more than 2/3 displayed psychiatric disorders, including depression, disruptive behaviors, anxiety, and bipolar/psychotic disorders. Psychiatric dimensions such as impulse control problems, attentional deficits, social problems, and aggressive behaviors were frequent features of FLE. Intellectual disability was associated with an earlier onset of psychiatric disorders and more frequent disruptive behavior disorders and aggressiveness. Long-standing epilepsy and bilateral or anterior frontal EEG abnormalities also increased the risk of psychopathology. Finally, right-hemisphere lesions were associated with disruptive behavior disorders, fast EEG rhythms with attention/memory problems, and phases of seizure remission with impulse control problems.

Conclusions: Clinical and EEG markers of increased psychopathological risk may help in defining consistent at-risk subgroups within FLE and improving early diagnosis, prognosis, and treatment. Categorical and dimensional approaches to psychiatric diagnosis may generate new research hypotheses and support the investigation of the complex pathophysiological bases shared by different neurodevelopmental disturbances.
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http://dx.doi.org/10.1016/j.yebeh.2019.01.008DOI Listing
March 2019

Transient Cognitive Impairment in Epilepsy.

Front Mol Neurosci 2018 7;11:458. Epub 2019 Jan 7.

NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Pisa, Italy.

Impairments of the dialog between excitation and inhibition (E/I) is commonly associated to neuropsychiatric disorders like autism, bipolar disorders and epilepsy. Moderate levels of hyperexcitability can lead to mild alterations of the EEG and are often associated with cognitive deficits even in the absence of overt seizures. Indeed, various testing paradigms have shown degraded performances in presence of acute or chronic non-ictal epileptiform activity. Evidences from both animal models and the clinics suggest that anomalous activity can cause cognitive deficits by transiently disrupting cortical processing, independently from the underlying etiology of the disease. Here, we will review our understanding of the influence of an abnormal EEG activity on brain computation in the context of the available clinical data and in genetic or pharmacological animal models.
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http://dx.doi.org/10.3389/fnmol.2018.00458DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6330286PMC
January 2019

encephalopathy: A distinctive generalized developmental and epileptic encephalopathy.

Neurology 2019 01 12;92(2):e96-e107. Epub 2018 Dec 12.

From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia.

Objective: To delineate the epileptology, a key part of the phenotypic spectrum, in a large patient cohort.

Methods: Patients were recruited via investigators' practices or social media. We included patients with (likely) pathogenic variants or chromosome 6p21.32 microdeletions incorporating . We analyzed patients' phenotypes using a standardized epilepsy questionnaire, medical records, EEG, MRI, and seizure videos.

Results: We included 57 patients (53% male, median age 8 years) with mutations (n = 53) or microdeletions (n = 4). Of the 57 patients, 56 had epilepsy: generalized in 55, with focal seizures in 7 and infantile spasms in 1. Median seizure onset age was 2 years. A novel type of drop attack was identified comprising eyelid myoclonia evolving to a myoclonic-atonic (n = 5) or atonic (n = 8) seizure. Seizure types included eyelid myoclonia with absences (65%), myoclonic seizures (34%), atypical (20%) and typical (18%) absences, and atonic seizures (14%), triggered by eating in 25%. Developmental delay preceded seizure onset in 54 of 56 (96%) patients for whom early developmental history was available. Developmental plateauing or regression occurred with seizures in 56 in the context of a developmental and epileptic encephalopathy (DEE). Fifty-five of 57 patients had intellectual disability, which was moderate to severe in 50. Other common features included behavioral problems (73%); high pain threshold (72%); eating problems, including oral aversion (68%); hypotonia (67%); sleeping problems (62%); autism spectrum disorder (54%); and ataxia or gait abnormalities (51%).

Conclusions: mutations cause a generalized DEE with a distinctive syndrome combining epilepsy with eyelid myoclonia with absences and myoclonic-atonic seizures, as well as a predilection to seizures triggered by eating.
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http://dx.doi.org/10.1212/WNL.0000000000006729DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6340340PMC
January 2019

Defining the electroclinical phenotype and outcome of PCDH19-related epilepsy: A multicenter study.

Epilepsia 2018 12 19;59(12):2260-2271. Epub 2018 Nov 19.

Neurology Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.

Objective: PCDH19-related epilepsy is an epileptic syndrome with infantile onset, characterized by clustered and fever-induced seizures, often associated with intellectual disability (ID) and autistic features. The aim of this study was to analyze a large cohort of patients with PCDH19-related epilepsy and better define the epileptic phenotype, genotype-phenotype correlations, and related outcome-predicting factors.

Methods: We retrospectively collected genetic, clinical, and electroencephalogram (EEG) data of 61 patients with PCDH19-related epilepsy followed at 15 epilepsy centers. All consecutively performed EEGs were analyzed, totaling 551. We considered as outcome measures the development of ID, autistic spectrum disorder (ASD), and seizure persistence. The analyzed variables were the following: gender, age at onset, age at study, genetic variant, fever sensitivity, seizure type, cluster occurrence, status epilepticus, EEG abnormalities, and cognitive and behavioral disorders. Receiver operating characteristic curve analysis was performed to evaluate the age at which seizures might decrease in frequency.

Results: At last follow-up (median = 12 years, range = 1.9-42.1 years), 48 patients (78.7%) had annual seizures/clusters, 13 patients (21.3%) had monthly to weekly seizures, and 12 patients (19.7%) were seizure-free for ≥2 years. Receiver operating characteristic analysis showed a significant decrease of seizure frequency after the age of 10.5 years (sensitivity = 81.0%, specificity = 70.0%). Thirty-six patients (59.0%) had ID and behavioral disturbances. ASD was present in 31 patients. An earlier age at epilepsy onset emerged as the only predictive factor for ID (P = 0.047) and ASD (P = 0.014). Conversely, age at onset was not a predictive factor for seizure outcome (P = 0.124).

Significance: We found that earlier age at epilepsy onset is related to a significant risk for ID and ASD. Furthermore, long-term follow-up showed that after the age of 10 years, seizures decrease in frequency and cognitive and behavioral disturbances remain the primary clinical problems.
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http://dx.doi.org/10.1111/epi.14600DOI Listing
December 2018

Understanding Spreading Depression from Headache to Sudden Unexpected Death.

Front Neurol 2018 1;9:19. Epub 2018 Feb 1.

Molecular Medicine and Clinical Neurophysiology Laboratories, Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, Pisa, Italy.

Spreading depression (SD) is a neurophysiological phenomenon characterized by abrupt changes in intracellular ion gradients and sustained depolarization of neurons. It leads to loss of electrical activity, changes in the synaptic architecture, and an altered vascular response. Although SD is often described as a unique phenomenon with homogeneous characteristics, it may be strongly affected by the particular triggering event and by genetic background. Furthermore, SD may contribute differently to the pathogenesis of widely heterogeneous clinical conditions. Indeed, clinical disorders related to SD vary in their presentation and severity, ranging from benign headache conditions (migraine syndromes) to severely disabling events, such as cerebral ischemia, or even death in people with epilepsy. Although the characteristics and mechanisms of SD have been dissected using a variety of approaches, ranging from cells to human models, this phenomenon remains only partially understood because of its complexity and the difficulty of obtaining direct experimental data. Currently, clinical monitoring of SD is limited to patients who require neurosurgical interventions and the placement of subdural electrode strips. Significantly, SD events recorded in humans display electrophysiological features that are essentially the same as those observed in animal models. Further research using existing and new experimental models of SD may allow a better understanding of its core mechanisms, and of their differences in different clinical conditions, fostering opportunities to identify and develop targeted therapies for SD-related disorders and their worst consequences.
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http://dx.doi.org/10.3389/fneur.2018.00019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5799941PMC
February 2018

Internalizing and externalizing symptoms in preschool and school-aged children with epilepsy: Focus on clinical and EEG features.

Epilepsy Behav 2018 02 15;79:68-74. Epub 2017 Dec 15.

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Via dei Giacinti 2, Calambrone, 56128 Pisa, Italy. Electronic address:

Introduction: Psychiatric and behavioral problems are frequent comorbidities of epilepsy, although their clinical and electroencephalographic (EEG) correlates remain uncertain. In this study, we have assessed the frequency of psychopathological problems in a cohort of children with epilepsy, and established their main clinical and EEG-associated features.

Methods: One hundred fifty-nine young patients with epilepsy were recruited and assessed through the Child Behavior Checklist for preschool-aged children (CBCL 1 1/2-5) or for school-aged children (CBCL 6-18). Child Behavior Checklist (CBCL) results were then correlated to the main clinical and EEG data.

Results: We found emotional and behavioral problems in about half of the children in our sample. Internalizing, social, and attention problems were more common than externalizing features. Moderate intellectual disability, a nonidiopathic etiology of epilepsy, a poor control of seizures, and antiepileptic polytherapies, as well as an early age at seizure-onset and a longer duration of the disorder, were all associated with specific behavioral and emotional problems. A temporal site of interictal EEG abnormalities also enhanced the risk for psychiatric comorbidities, especially in the externalizing domain.

Conclusions: Several clinical and EEG features are associated with an increased risk for emotional and behavioral comorbidities in children with epilepsy. Their identification may foster an early diagnosis and appropriate care, limiting the worsening of psychiatric symptoms and their impact on quality of life and health status. A better understanding of the underlying clinical and molecular mechanisms is needed to further improve prevention and treatment interventions.
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http://dx.doi.org/10.1016/j.yebeh.2017.10.004DOI Listing
February 2018

An integrated EEG and eye-tracking approach for the study of responding and initiating joint attention in Autism Spectrum Disorders.

Sci Rep 2017 10 19;7(1):13560. Epub 2017 Oct 19.

IRCCS Stella Maris Foundation, Viale del Tirreno 331, 56018, Calambrone, (PI), Italy.

Autism Spectrum Disorders (ASD) are characterised by impairment in joint attention (JA), which has two components: the response to JA and the initiation of JA. Literature suggests a correlation between JA and neural circuitries, although this link is still largely unexplored in ASD. In this pilot study, we aimed at investigating the neural correlates of responding and initiating JA in high-functioning children with ASD and evaluating the changes in brain function and visual pattern after six months of rehabilitative treatment using an integrated EEG/eye-tracking system. Our results showed that initiating and responding JA subtend both overlapping (i.e. frontal and temporal) and specialized (i.e. parietal for responding JA and occipital for initiating JA) neural circuitries. In addition, in a subgroup of subjects, we observed trends of changes in both brain activity and connectivity after rehabilitative treatment in both the two tasks, which were correlated with modifications in gaze measures. These preliminary results, if confirmed in a larger sample, suggest the feasibility of using the proposed multimodal approach to characterise JA-related brain circuitries and visual pattern in ASD individuals and to monitor longitudinal changes in response to rehabilitative intervention.
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http://dx.doi.org/10.1038/s41598-017-13053-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5648821PMC
October 2017

Benign infantile seizures followed by autistic regression in a boy with 16p11.2 deletion.

Epileptic Disord 2017 Jun;19(2):222-225

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy.

Benign infantile seizures (BIS) are usually a self-limiting condition, which may be associated with heterozygous mutations in the PRRT2 gene at chromosome 16p11.2. Here, we report a boy with a deletion in 16p11.2, presenting with BIS and typical neurodevelopment in the first year of life, unexpectedly followed by severe autistic regression. 16p11.2 deletions are typically associated with intellectual disability, autism, and language disorders, and only rarely with BIS. This clinical report shows that the neurodevelopmental prognosis in BIS patients may not always be benign, and suggests that array CGH screening should be considered for affected infants in order to rule out deletions at 16p11.2 and long-term clinical follow-up.
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http://dx.doi.org/10.1684/epd.2017.0909DOI Listing
June 2017

Clinical and genetic factors predicting Dravet syndrome in infants with mutations.

Neurology 2017 Mar 15;88(11):1037-1044. Epub 2017 Feb 15.

From the Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories (V.C., S.C., D.M., E.P., C.M., D.P., R.G.), Neuroscience Department, A Meyer Children's Hospital, University of Florence; Department of Statistics, Computer Science and Applications (L.G.), University of Florence; Division of Child Neurology and Psychiatry Epilepsy and Clinical Neurophysiology Laboratory (A.F., F.S., R.G.), IRCCS Stella Maris Foundation, Pisa; Department of Neurosciences (N.S., M.T.), Neurology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome; Child Neuropsichiatry Fondazione Policlinico Universitario Agostino Gemelli (D.B., I.C.), Università Cattolica del Sacro Cuore, Rome; Child Neuropsychiatry Unit (N.Z., C.P.), Ospedali Riuniti, Ancona; and Department of Pediatric Neuroscience (T.G., F.R., G.A.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy.

Objective: To explore the prognostic value of initial clinical and mutational findings in infants with mutations.

Methods: Combining sex, age/fever at first seizure, family history of epilepsy, EEG, and mutation type, we analyzed the accuracy of significant associations in predicting Dravet syndrome vs milder outcomes in 182 mutation carriers ascertained after seizure onset. To assess the diagnostic accuracy of all parameters, we calculated sensitivity, specificity, receiver operating characteristic (ROC) curves, diagnostic odds ratios, and positive and negative predictive values and the accuracy of combined information. We also included in the study demographic and mutational data of the healthy relatives of mutation carrier patients.

Results: Ninety-seven individuals (48.5%) had Dravet syndrome, 49 (23.8%) had generalized/genetic epilepsy with febrile seizures plus, 30 (14.8%) had febrile seizures, 6 (3.5%) had focal epilepsy, and 18 (8.9%) were healthy relatives. The association study indicated that age at first seizure and frameshift mutations were associated with Dravet syndrome. The risk of Dravet syndrome was 85% in the 0- to 6-month group, 51% in the 6- to 12-month range, and 0% after the 12th month. ROC analysis identified onset within the sixth month as the diagnostic cutoff for progression to Dravet syndrome (sensitivity = 83.3%, specificity = 76.6%).

Conclusions: In individuals with mutations, age at seizure onset appears to predict outcome better than mutation type. Because outcome is not predetermined by genetic factors only, early recognition and treatment that mitigates prolonged/repeated seizures in the first year of life might also limit the progression to epileptic encephalopathy.
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http://dx.doi.org/10.1212/WNL.0000000000003716DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5384833PMC
March 2017

Gain-of-function defects of astrocytic Kir4.1 channels in children with autism spectrum disorders and epilepsy.

Sci Rep 2016 Sep 28;6:34325. Epub 2016 Sep 28.

School of Medicine, Section of Physiology &Biochemistry, Department of Experimental Medicine, Piazzale Gambuli, University of Perugia, 06132-Perugia, Italy.

Dysfunction of the inwardly-rectifying potassium channels Kir4.1 (KCNJ10) represents a pathogenic mechanism contributing to Autism-Epilepsy comorbidity. To define the role of Kir4.1 variants in the disorder, we sequenced KCNJ10 in a sample of affected individuals, and performed genotype-phenotype correlations. The effects of mutations on channel activity, protein trafficking, and astrocyte function were investigated in Xenopus laevis oocytes, and in human astrocytoma cell lines. An in vivo model of the disorder was also explored through generation of kcnj10a morphant zebrafish overexpressing the mutated human KCNJ10. We detected germline heterozygous KCNJ10 variants in 19/175 affected children. Epileptic spasms with dysregulated sensory processing represented the main disease phenotype. When investigated on astrocyte-like cells, the p.R18Q mutation exerted a gain-of-function effect by enhancing Kir4.1 membrane expression and current density. Similarly, the p.R348H variant led to gain of channel function through hindrance of pH-dependent current inhibition. The frequent polymorphism p.R271C seemed, instead, to have no obvious functional effects. Our results confirm that variants in KCNJ10 deserve attention in autism-epilepsy, and provide insight into the molecular mechanisms of autism and seizures. Similar to neurons, astrocyte dysfunction may result in abnormal synaptic transmission and electrical discharge, and should be regarded as a possible pharmacological target in autism-epilepsy.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5039625PMC
http://dx.doi.org/10.1038/srep34325DOI Listing
September 2016

The Revolution in Migraine Genetics: From Aching Channels Disorders to a Next-Generation Medicine.

Front Cell Neurosci 2016 13;10:156. Epub 2016 Jun 13.

Molecular Medicine, IRCCS Stella Maris Foundation Pisa, Italy.

Channelopathies are a heterogeneous group of neurological disorders resulting from dysfunction of ion channels located in cell membranes and organelles. The clinical scenario is broad and symptoms such as generalized epilepsy (with or without fever), migraine (with or without aura), episodic ataxia and periodic muscle paralysis are some of the best known consequences of gain- or loss-of-function mutations in ion channels. We review the main clinical effects of ion channel mutations associated with a significant impact on migraine headache. Given the increasing and evolving use of genetic analysis in migraine research-greater emphasis is now placed on genetic markers of dysfunctional biological systems-we also show how novel information in rare monogenic forms of migraine might help to clarify the disease mechanisms in the general population of migraineurs. Next-generation sequencing (NGS) and more accurate and precise phenotyping strategies are expected to further increase understanding of migraine pathophysiology and genetics.
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http://dx.doi.org/10.3389/fncel.2016.00156DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4904011PMC
July 2016

Focal cortical dysplasia, microcephaly and epilepsy in a boy with 1q21.1-q21.3 duplication.

Eur J Med Genet 2016 May 11;59(5):278-82. Epub 2016 Mar 11.

IRCCS Stella Maris Foundation, Department of Developmental Neuroscience, Pisa, Italy. Electronic address:

The recent advance of new molecular technologies like array - Comparative Genomic Hybridization has fostered the detection of genomic imbalances in subjects with intellectual disability, epilepsy, and/or congenital anomalies. Though some of the rearrangements are relatively frequent, their consequences on phenotypes can be strongly variable. We report on a boy harbouring a de novo 8.3 Mb duplication of chromosome 1q21.1-q21.3 whose complex unusual phenotype deserves attention, due to the presence of focal cortical dysplasia, microcephaly, and epilepsy. Loss-of-function (LOF) effects of genes associated with human disease involved in the rearrangement have been only partially established, and have not been previously associated with brain malformations in several deletion syndromes. Less is known, instead, about the consequences of their duplication on neuronal migration and brain development process. Further advance in neuroimaging and genetic research will help in defining their actual role in neurodevelopment and cerebral cortex malformations.
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http://dx.doi.org/10.1016/j.ejmg.2016.03.003DOI Listing
May 2016

Epilepsy, Behavioral Abnormalities, and Physiological Comorbidities in Syntaxin-Binding Protein 1 (STXBP1) Mutant Zebrafish.

PLoS One 2016 10;11(3):e0151148. Epub 2016 Mar 10.

Department of Neurological Surgery, University of California San Francisco, San Francisco, California, United States of America.

Mutations in the synaptic machinery gene syntaxin-binding protein 1, STXBP1 (also known as MUNC18-1), are linked to childhood epilepsies and other neurodevelopmental disorders. Zebrafish STXBP1 homologs (stxbp1a and stxbp1b) have highly conserved sequence and are prominently expressed in the larval zebrafish brain. To understand the functions of stxbp1a and stxbp1b, we generated loss-of-function mutations using CRISPR/Cas9 gene editing and studied brain electrical activity, behavior, development, heart physiology, metabolism, and survival in larval zebrafish. Homozygous stxbp1a mutants exhibited a profound lack of movement, low electrical brain activity, low heart rate, decreased glucose and mitochondrial metabolism, and early fatality compared to controls. On the other hand, homozygous stxbp1b mutants had spontaneous electrographic seizures, and reduced locomotor activity response to a movement-inducing "dark-flash" visual stimulus, despite showing normal metabolism, heart rate, survival, and baseline locomotor activity. Our findings in these newly generated mutant lines of zebrafish suggest that zebrafish recapitulate clinical phenotypes associated with human syntaxin-binding protein 1 mutations.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0151148PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4786103PMC
August 2016

Targeted Gene Resequencing (Astrochip) to Explore the Tripartite Synapse in Autism-Epilepsy Phenotype with Macrocephaly.

Neuromolecular Med 2016 Mar 4;18(1):69-80. Epub 2015 Nov 4.

Molecular Medicine, IRCCS Stella Maris Foundation, Viale del Tirreno 331, via dei Giacinti 2, 56128, Calambrone, Pisa, Italy.

The frequent co-occurrence of autism spectrum disorders (ASD) and epilepsy, or paroxysmal EEG abnormalities, defines a condition termed autism-epilepsy phenotype (AEP). This condition results, in some cases , from dysfunctions of glial inwardly rectifying potassium channels (Kir), which are mainly expressed in astrocytes where they mediate neuron-glia communication. Macrocephaly is also often comorbid with autism-epilepsy (autism-epilepsy phenotype with macrocephaly, MAEP), and it is tempting to hypothesize that shared pathogenic mechanisms might explain concurrence of these conditions. In the present study, we assessed whether protein pathways involved, along with Kir channels, in astrocyte-neuron interaction at the tripartite synapse play a role in the etiopathogenesis of MAEP. Using a targeted resequencing methodology, we investigated the coding regions of 35 genes in 61 patients and correlated genetic results with clinical features. Variants were subdivided into 12 classes and clustered into four groups. We detected rare or previously unknown predicted deleterious missense changes in GJA1, SLC12A2, SNTA1, EFNA3, CNTNAP2, EPHA4, and STXBP1 in seven patients and two high-frequency variants in DLG1 in six individuals. We also found that a group of variants (predicted deleterious and non-coding), segregating with the comorbid MAEP/AEP subgroups, belong to proteins specifically involved in glutamate transport and metabolism (namely, SLC17A6, GRM8, and GLUL), as well as in potassium conductance (KCNN3). This "endophenotype-oriented" study, performed using a targeted strategy, helped to further delineate part of the complex genetic background of ASD, particularly in the presence of coexisting macrocephaly and/or epilepsy/paroxysmal EEG, and suggests that use of stringent clinical clustering might be an approach worth adopting in order to unravel the complex genomic data in neurodevelopmental disorders.
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http://dx.doi.org/10.1007/s12017-015-8378-2DOI Listing
March 2016

Temporal lobe connects regression and macrocephaly to autism spectrum disorders.

Eur Child Adolesc Psychiatry 2016 Apr 30;25(4):421-9. Epub 2015 Jul 30.

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Via dei Giacinti 2 - Calambrone, 56128, Pisa, Italy.

Interictal electroencephalogram (EEG) abnormalities are frequently associated with autism spectrum disorders (ASD), although their relationship with the clinical features of ASD, particularly the regressive onset, remains controversial. The aim of this study was to investigate whether the characteristics of interictal EEG abnormalities might help to distinguish and predict definite phenotypes within the heterogeneity of ASD. We reviewed the awake and sleep interictal EEGs of 220 individuals with idiopathic ASD, either with or without a history of seizures. EEG findings were analyzed with respect to a set of clinical variables to explore significant associations. A brain morphometry study was also carried out on a subgroup of patients. EEG abnormalities were seen in 154/220 individuals (70%) and were mostly focal (p < 0.01) with an anterior localization (p < 0.001). They were detected more frequently during sleep (p < 0.01), and were associated with a regressive onset of ASD (p < 0.05), particularly in individuals with focal temporal localization (p < 0.05). This association was also stronger in regressive patients with concurrent macrocephaly, together with a relative volumetric reduction of the right temporal cortex (p < 0.05). Indeed, concurrence of temporal EEG abnormalities, regression and macrocephaly might possibly define a distinct endophenotype of ASD. EEG-based endophenotypes could be useful to untangle the complexity of ASD, helping to establish anatomic or pathophysiologic subtypes of the disorder.
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http://dx.doi.org/10.1007/s00787-015-0746-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4820486PMC
April 2016

Mitochondrial respiratory chain defects in skin fibroblasts from patients with Dravet syndrome.

Neurol Sci 2015 Nov 14;36(11):2151-5. Epub 2015 Jul 14.

Molecular Medicine, IRCCS Stella Maris, via dei Giacinti 2, 56128, Calambrone-Pisa, Italy.

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http://dx.doi.org/10.1007/s10072-015-2324-9DOI Listing
November 2015

Classification of autism spectrum disorder using supervised learning of brain connectivity measures extracted from synchrostates.

J Neural Eng 2014 Aug 1;11(4):046019. Epub 2014 Jul 1.

School of Electronics and Computer Science, University of Southampton, Southampton SO17 1BJ, UK.

Objective: The paper investigates the presence of autism using the functional brain connectivity measures derived from electro-encephalogram (EEG) of children during face perception tasks.

Approach: Phase synchronized patterns from 128-channel EEG signals are obtained for typical children and children with autism spectrum disorder (ASD). The phase synchronized states or synchrostates temporally switch amongst themselves as an underlying process for the completion of a particular cognitive task. We used 12 subjects in each group (ASD and typical) for analyzing their EEG while processing fearful, happy and neutral faces. The minimal and maximally occurring synchrostates for each subject are chosen for extraction of brain connectivity features, which are used for classification between these two groups of subjects. Among different supervised learning techniques, we here explored the discriminant analysis and support vector machine both with polynomial kernels for the classification task.

Main Results: The leave one out cross-validation of the classification algorithm gives 94.7% accuracy as the best performance with corresponding sensitivity and specificity values as 85.7% and 100% respectively.

Significance: The proposed method gives high classification accuracies and outperforms other contemporary research results. The effectiveness of the proposed method for classification of autistic and typical children suggests the possibility of using it on a larger population to validate it for clinical practice.
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http://dx.doi.org/10.1088/1741-2560/11/4/046019DOI Listing
August 2014

Late-onset epileptic spasms: clinical evidence and outcome in 34 patients.

J Child Neurol 2015 Feb 6;30(2):153-9. Epub 2014 Jun 6.

Epilepsy and Clinical Neurophysiology Laboratory, Department of Clinical Neuroscience, IRCCS Stella Maris Foundation, Calambrone, Pisa, Italy

To evaluate the diverse presentation and course of late-onset epileptic spasms in relation to etiology, we analyzed the clinical, electroencephalographic (EEG), and prognostic features in 34 patients. We divided the patient sample into cryptogenic or symptomatic based on etiology. An association emerged between symmetric spasms at onset and focal interictal EEG abnormalities in cryptogenic patients, and onset with focal or generalized seizures before displaying asymmetric spasms, and multifocal or diffuse EEG abnormalities, in the symptomatic group. Despite an overall poor prognosis, symptomatic patients starting with generalized seizures seem to have a relatively more favorable outcome. The high occurrence of intellectual disability, and sometimes psychomotor regression, confirmed this rare and poorly understood heterogeneous clinical condition as a severe form of epileptic encephalopathy that deserves further study.
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http://dx.doi.org/10.1177/0883073814532547DOI Listing
February 2015

Genetically induced dysfunctions of Kir2.1 channels: implications for short QT3 syndrome and autism-epilepsy phenotype.

Hum Mol Genet 2014 Sep 2;23(18):4875-86. Epub 2014 May 2.

Faculty of Medicine, Section of Physiology & Biochemistry, Department of Experimental Medicine.

Short QT3 syndrome (SQT3S) is a cardiac disorder characterized by a high risk of mortality and associated with mutations in Kir2.1 (KCNJ2) channels. The molecular mechanisms leading to channel dysfunction, cardiac rhythm disturbances and neurodevelopmental disorders, potentially associated with SQT3S, remain incompletely understood. Here, we report on monozygotic twins displaying a short QT interval on electrocardiogram recordings and autism-epilepsy phenotype. Genetic screening identified a novel KCNJ2 variant in Kir2.1 that (i) enhanced the channel's surface expression and stability at the plasma membrane, (ii) reduced protein ubiquitylation and degradation, (iii) altered protein compartmentalization in lipid rafts by targeting more channels to cholesterol-poor domains and (iv) reduced interactions with caveolin 2. Importantly, our study reveals novel physiological mechanisms concerning wild-type Kir2.1 channel processing by the cell, such as binding to both caveolin 1 and 2, protein degradation through the ubiquitin-proteasome pathway; in addition, it uncovers a potential multifunctional site that controls Kir2.1 surface expression, protein half-life and partitioning to lipid rafts. The reported mechanisms emerge as crucial also for proper astrocyte function, suggesting the need for a neuropsychiatric evaluation in patients with SQT3S and offering new opportunities for disease management.
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http://dx.doi.org/10.1093/hmg/ddu201DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4140467PMC
September 2014

Autism-epilepsy phenotype with macrocephaly suggests PTEN, but not GLIALCAM, genetic screening.

BMC Med Genet 2014 Feb 27;15:26. Epub 2014 Feb 27.

Clinical Neurophysiology Laboratory, IRCCS Stella Maris Foundation, Viale del Tirreno 331, Pisa, Calambrone 56128, Italy.

Background: With a complex and extremely high clinical and genetic heterogeneity, autism spectrum disorders (ASD) are better dissected if one takes into account specific endophenotypes. Comorbidity of ASD with epilepsy (or paroxysmal EEG) has long been described and seems to have strong genetic background. Macrocephaly also represents a well-known endophenotype in subgroups of ASD individuals, which suggests pathogenic mechanisms accelerating brain growth in early development and predisposing to the disorder. We attempted to estimate the association of gene variants with neurodevelopmental disorders in patients with autism-epilepsy phenotype (AEP) and cranial overgrowth, analyzing two genes previously reported to be associated with autism and macrocephaly.

Methods: We analyzed the coding sequences and exon-intron boundaries of GLIALCAM, encoding an IgG-like cell adhesion protein, in 81 individuals with Autism Spectrum Disorders, either with or without comorbid epilepsy, paroxysmal EEG and/or macrocephaly, and the PTEN gene in the subsample with macrocephaly.

Results: Among 81 individuals with ASD, 31 had concurrent macrocephaly. Head circumference, moreover, was over the 99.7th percentile ("extreme" macrocephaly) in 6/31 (19%) patients. Whilst we detected in GLIALCAM several single nucleotide variants without clear pathogenic effects, we found a novel PTEN heterozygous frameshift mutation in one case with "extreme" macrocephaly, autism, intellectual disability and seizures.

Conclusions: We did not find a clear association between GLIALCAM mutations and AEP-macrocephaly comorbidity. The identification of a novel frameshift variant of PTEN in a patient with "extreme" macrocephaly, autism, intellectual disability and seizures, confirms this gene as a major candidate in the ASD-macrocephaly endophenotype. The concurrence of epilepsy in the same patient also suggests that PTEN, and the downstream signaling pathway, might deserve to be investigated in autism-epilepsy comorbidity. Working on clinical endophenotypes might be of help to address genetic studies and establish actual causative correlations in autism-epilepsy.
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http://dx.doi.org/10.1186/1471-2350-15-26DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3941568PMC
February 2014

MECP2 duplication phenotype in symptomatic females: report of three further cases.

Mol Cytogenet 2014 Jan 28;7(1):10. Epub 2014 Jan 28.

Department of Molecular Medicine, University of Pavia, Pavia, Italy.

Background: Xq28 duplications, including MECP2 (methyl CpG-binding protein 2; OMIM 300005), have been identified in approximately 140 male patients presenting with hypotonia, severe developmental delay/intellectual disability, limited or absent speech and ambulation, and recurrent respiratory infections. Female patients with Xq28 duplication have been rarely reported and are usually asymptomatic. Altogether, only fifteen symptomatic females with Xq28 duplications including MECP2 have been reported so far: six of them had interstitial duplications while the remaining had a duplication due to an unbalanced X;autosome translocation. Some of these females present with unspecific mild to moderate intellectual disability whereas a more complex phenotype is reported for females with unbalanced X;autosome translocations.

Findings: Here we report on the clinical features of three other adolescent to adult female patients with Xq28 interstitial duplications of variable size, all including MECP2 gene.

Conclusions: Mild to moderate cognitive impairment together with learning difficulties and speech delay were evident in each of our patients. Moreover, early inadequate behavioral patterns followed by persistent difficulties in the social and communication domains, as well as the occurrence of mild psychiatric disturbances, are common features of these three patients.
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http://dx.doi.org/10.1186/1755-8166-7-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3922903PMC
January 2014