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Pathogenic loss-of-function variants in the IQ motif and SEC7 domain containing protein 2 (IQSEC2) gene cause intellectual disability with Rett syndrome (RTT)-like features. The aim of this study was to obtain systematic information on the natural history and extra-central nervous system (CNS) manifestations for the Italian IQSEC2 population (>90%) by using structured family interviews and semi-quantitative questionnaires. IQSEC2 encephalopathy prevalence estimate was 7.0 to 7.9 × 10−7. Criteria for typical RTT were met in 42.1% of the cases, although psychomotor regression was occasionally evidenced. Genetic diagnosis was occasionally achieved in infancy despite a clinical onset before the first 24 months of life. High severity in both the CNS and extra-CNS manifestations for the IQSEC2 patients was documented and related to a consistently adverse quality of life. Neurodevelopmental delay was diagnosed before the onset of epilepsy by 1.8 to 2.4 years. An earlier age at menarche in IQSEC2 female patients was reported. Sleep disturbance was highly prevalent (60 to 77.8%), with mandatory co-sleeping behavior (50% of the female patients) being related to de novo variant origin, younger age, taller height with underweight, better social interaction, and lower life quality impact for the family and friends area. In conclusion, the IQSEC2 encephalopathy is a rare and likely underdiagnosed developmental encephalopathy leading to an adverse life quality impact. [ABSTRACT FROM AUTHOR]

Nicolaides–Baraitser syndrome (NCBRS), caused by a mutation in the SMARCA2 gene, which goes along with intellectual disability, congenital malformations, especially of face and limbs, and often difficult-to-treat epilepsy, is surveyed focusing on epilepsy and its treatment. Patients were recruited via "Network Therapy of Rare Epilepsies (NETRE)" and an international NCBRS parent support group. Inclusion criterion is NCBRS-defining SMARCA2 mutation. Clinical findings including epilepsy classification, anticonvulsive treatment, electroencephalogram (EEG) findings, and neurodevelopmental outcome were collected with an electronic questionnaire. Inclusion of 25 NCBRS patients with epilepsy in 23 of 25. Overall, 85% of the participants (17/20) reported generalized seizures, the semiology varied widely. EEG showed generalized epileptogenic abnormalities in 53% (9/17), cranial magnetic resonance imaging (cMRI) was mainly inconspicuous. The five most frequently used anticonvulsive drugs were valproic acid (VPA [12/20]), levetiracetam (LEV [12/20]), phenobarbital (PB [8/20]), topiramate (TPM [5/20]), and carbamazepine (CBZ [5/20]). LEV (9/12), PB (6/8), TPM (4/5), and VPA (9/12) reduced the seizures' frequency in more than 50%. Temporary freedom of seizures (>6 months) was reached with LEV (4/12), PB (3/8), TPM (1/5, only combined with PB and nitrazepam [NZP]), and VPA (4/12). Seizures aggravation was observed under lamotrigine (LTG [2/4]), LEV (1/12), PB (1/8), and VPA (1/12). Ketogenic diet (KD) and vagal nerve stimulation (VNS) reduced seizures' frequency in one of two each. This first worldwide retrospective analysis of anticonvulsive therapy in NCBRS helps to treat epilepsy in NCBRS that mostly shows only initial response to anticonvulsive therapy, especially with LEV and VPA, but very rarely shows complete freedom of seizures in this, rather genetic than structural epilepsy. [ABSTRACT FROM AUTHOR]

Introduction: Berardinelli-Seip syndrome or congenital generalized lipodystrophy type 2 is a rare genetic disorder characterized by selective loss of subcutaneous adipose tissue associated with peripheral insulin resistance and its complications. Nonprogressive mental retardation, dystonia, ataxia, and pyramidal signs are commonly present, whereas epilepsy has only occasionally been observed.Case Report: We report the case of two sisters, 11 and 18 years old respectively, with an overlapping clinical phenotype compatible with Berardinelli-Seip syndrome and progressive myoclonic epilepsy. Molecular analysis identified an autosomal recessive c.1048C > t;(p(Arg350*)) pathogenic mutation of exon 8 of the BSCL2 gene, which was present in a homozygous state in both patients.Conclusions: Our paper contributes to further delineate a complex phenotype associated with BSCL2 mutation, underlining how seipin has a central and partially still unknown role that goes beyond adipose tissue metabolism, with a prominent involvement in central nervous system pathology. [ABSTRACT FROM AUTHOR]

Introduction: The short arm of chromosome 17 is characterized by a high density of low copy repeats, creating the opportunity for non-allelic homologous recombination to occur. Microdeletions of the 17p13.3 region are responsible for neuronal migration disorders including isolated lissencephaly sequence and Miller-Dieker syndrome. Case report: We describe the case of a 4-year and 2-month-old female with peculiar somatic traits and neurodevelopmental delay. At the age of 6 months, she started to present with infantile spasms syndrome; therefore, we administered vigabatrin followed by two cycles of adrenocorticotropic hormone, with good response. The coexistence of epileptic activity, neuropsychological delay, brain imaging abnormalities, and peculiar somatic features oriented us towards the hypothesis of a genetic etiology that could explain her clinical picture. Array CGH identified a 730 Kb deletion in the p13.3 region of the short arm of chromosome 17 including eleven genes, among these are YWHAE and CRK. Discussion: Microdeletions of the 17p13.3 region involving only YWHAE and CRK, sparing PAFAH1B1, result in neurodevelopmental delay, growth retardation, craniofacial dysmorphisms, and mild structural brain abnormalities. Differently from the previously described patients carrying YWHAE and CRK deletions, the main complaint of our patient was represented by seizures. The absence of clear neuronal migration defects and mutations of the PAFAH1B1 gene in our patient underlines the central role of additional genes located in the 17p13.3 chromosomal region in the pathogenesis of epilepsy and helps to expand the phenotype of 17p13.3 microdeletion syndrome. [ABSTRACT FROM AUTHOR]

Purpose We investigated drugs most often used to treat epilepsy in Rett Syndrome and their efficacy in a large cohort of Italian patients. Methods This is a multi-centre retrospective study. Data of 165 Rett subjects were collected from the patients' files, and hospital charts. The efficacy of antiepileptic drugs (AEDs) was classified as follows: not effective; decrease in seizure frequency ≥50% for at least 6 months; seizure-free for at least 2 years. Phenotypic and genetic categorization of patients was performed and it was considered in AEDs efficacy evaluation. Results There were 130 epileptic patients.Sodium valproate (VPA) was the most commonly administered AED (44.3%) at seizure onset, followed by Carbamazepine (CBZ) (25.4%) and Phenobarbital (PB) (13%). Monotherapy was the first treatment option in most patients. VPA and CBZ proved to be equally effective in Rett patients who presented seizures within the typical age range (4–5 years), while Lamotrigine (LTG) was effective for patients in whom epilepsy started later. Overall, the frequency of side effects was low and the most often observed ones were restlessness and somnolence. Conclusion Our study suggests that LTG, VPA and CBZ can be used as drugs of first choice in Rett Syndrome. The association of four drugs should be avoided since it did not result in any significant clinical improvement. [ABSTRACT FROM AUTHOR]

Phosphatase and tensin homolog (PTEN) gene mutations are associated with a spectrum of clinical disorders characterized by skin lesions, macrocephaly, hamartomatous overgrowth of tissues, and an increased risk of cancers. Autism has rarely been described in association with these variable clinical features. At present, 24 patients with phosphatase and tensin homolog gene mutation, autism, macrocephaly, and some clinical findings described in phosphatase and tensin homolog syndromes have been reported in the literature. We describe a 14-year-old boy with autistic disorder, focal epilepsy, severe and progressive macrocephaly, and multiple papular skin lesions and palmoplantar punctate keratoses, characteristic of Cowden syndrome. The boy has a de novo phosphatase and tensin homolog gene mutation. Our patient is the first case described to present a typical Cowden syndrome and autism associated with epilepsy. [ABSTRACT FROM AUTHOR]

Rett syndrome is an X-linked dominant neurological disorder, which appears to be the commonest genetic cause of profound combined intellectual and physical disability in Caucasian females. Recently, this syndrome has been associated with mutations of the MECP2 gene, a transcriptional repressor of still unknown target genes. Here we report a detailed mutational analysis of 62 patients from UK and Italian archives, representing the first comparative study among different populations and one of the largest number of cases so far analyzed. We review the literature on MECP2 mutations in Rett syndrome. This analysis has permitted us to produce a map of the recurrent mutations identified in this and previous studies. Bioinformatic analysis of the mutations, taking advantage of structural and evolutionary data, leads us to postulate the existence of a new functional domain in the MeCP2 protein, which is conserved among brain-specific regulatory factors. [ABSTRACT FROM AUTHOR]

Background Neurodevelopmental disorders include a broad spectrum of conditions, which are characterized by delayed motor and/or cognitive milestones and by a variable range of intellectual disability with or without an autistic behavior. Several genetic factors have been implicated in intellectual disability onset and exome sequencing studies have recently identified new inherited or de novo mutations in patients with neurodevelopmental disorders. Case We report the case of two monozygotic twins who came for the first time to our attention at the age of 20 months for a global neurodevelopmental delay associated with an autism spectrum disorder, hypotonia, postnatal microcephaly, stereotypic movements and circadian rhythm alterations in association with late-onset epilepsy. MECP2 sequence was normal. A CGH-array analysis revealed in both twins two maternally inherited duplications on chromosomes 8p22 and 16p13.11. The latter has been previously associated with neurodevelopmental disorders. We performed an exome sequencing analysis on one twin and her parents and identified a CHD2 mutation, previously described in association with a phenotypic spectrum overlapping our patients’ phenotype. Conclusions This work underlines the importance to consider a CHD2 involvement in children with intellectual disability and autism spectrum disorder even in the absence of epilepsy at an early age. It also highlights the necessity to re-evaluate inherited copy number variants with low penetrance and/or high phenotypic variability because an underlying de novo molecular event can be the major cause of the phenotype. This is essential in order to reach a correct diagnosis and provide the couple with a proper recurrence risk. [ABSTRACT FROM AUTHOR]

Abstract: Microdeletions in the 15q22 region have not been well documented. We collected genotype and phenotype data from five patients with microdeletions involving 15q22.2, which were between 0.7 Mb and 6.5 Mb in size; two were of de novo origin and one was of familial origin. Intellectual disability and epilepsy are frequently observed in patients with 15q22.2 deletions. Genotype-phenotype correlation analysis narrowed the critical region for such neurologic symptoms to a genomic region of 654 Kb including the NMDA receptor-regulated 2 gene (NARG2) and the PAR-related orphan receptor A gene (RORA), either of which may be responsible for neurological symptoms commonly observed in patients with deletions in this region. The neighboring regions, including the forkhead box B1 gene (FOXB1), may also be related to the additional neurological features observed in the patients with larger deletions. [Copyright &y& Elsevier]

Abstract: Epilepsy often occurs in Rett syndrome and is considered a major problem. The aim of this study was to define the clinical features of epilepsy and the correlation between seizures and both genotype and clinical phenotype in the Rett population. One hundred sixty-five patients with Rett syndrome referred to four Italian centers were recruited. All patients underwent video/EEG monitoring and molecular analysis of the MECP2 gene or, in negative cases, of the CDKL5 and FOXG1 genes. The frequency of epilepsy was 79%. Drug-resistant epilepsy occurred in 30% of all our patients with Rett syndrome and in 38% of those with epilepsy. Our findings demonstrate that epilepsy differs among the various phenotypes and genotypes with respect to age at onset, drug responsiveness, and seizure semiology. The Hanefeld and preserved speech variants represent the extremes of the range of severity of epilepsy: the preserved speech variant is characterized by the mildest epileptic phenotype as epilepsy is much less frequent, starts later, and is less drug resistant than what is observed in the other phenotypes. Another important finding is that seizure onset before 1year of age and daily frequency are risk factors for drug resistance. Thus, this study should help clinicians provide better clinical counseling to the families of patients with Rett syndrome. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To assess the presence/absence of peculiar EEG features and epilepsy in MECP2-mutated Rett patients with the Zappella–Rett variant (Z-RTT) also known as preserved speech variant. Methods: Retrospective analysis of 16 (age 19.4±8.4years; range 8–38years) MECP2 mutated Z-RTT cases, including 11 high or intermediate performance (HIP), and five low-performance (LP) patients was performed. Peculiar EEG features were analyzed as a function of the HIP or LP Z-RTT categories: (1) centro-temporal spikes, (2) multifocal EEG activity, (3) EEG encephalopathy (i.e. multifocal EEG activity associated with the presence of background slowing and diffuse slow activity), (4) spindles and K-complex. Furthermore, we assessed the occurrence of epilepsy. Correlations between electroclinical features and category of Z-RTT genotype (missense or truncation mutation) were also tested. Results: The Z-RTT HIP group showed a very abnormal EEG (presence of centro-temporal spikes: p =0.004808), although the cases studied were not epileptogenic and did not develop encephalopathy. The LP group showed multifocal EEG activity (p =0.000229), EEG encephalopathy (p =0.000229) and epilepsy (p =0.299451). No significant differences between the prevalence of centro-temporal spikes, multifocal EEG activity, EEG encephalopathy, and epilepsy between the patients with the truncation or missense mutation were observed. Conclusions: EEG electrophysiological patterns and epileptogenic susceptibility differ in Z-RTT according to the level of performance (i.e. HIP or LP). Significance: These results indicate that HIP and LP Z-RTT should be considered as distinct entities, not only on a clinical basis, but also as it concerns EEG features and epileptogenic susceptibility. These results could offer support in the practical management of patients and family counseling. [Copyright &y& Elsevier]

Summary: Epilepsy and electroencephalographic (EEG) anomalies are common in subjects carrying chromosomal aberrations. We report clinical and EEG investigations on 13 patients carrying chromosome 2 anomalies, including two patients with inversions, six with translocations, two with partial duplications and three with interstitial deletion syndromes. Epilepsy and/or EEG anomalies were found in one patient with a chromosome 2 translocation, in both of those carrying partial duplications and in all three with interstitial deletion syndromes. No epilepsy or EEG anomalies were detected in the remaining patients. Conclusions: Epilepsy may be associated with chromosome 2 aberrations. Gross rearrangements involving the long arm of chromosome 2 might be more often associated with epilepsy than those involving the short arm. The association of epilepsy with chromosome 2 duplications is less clear. In particular, our observations and a review of the literature appear to suggest that a strict relationship between epilepsy and interstitial deletions involving the 2q24–q31 region. In the latter disorder tonic and focal seizures occur early in life. Generalized and focal myoclonic jerks tend to appear in infancy and are subsequently followed by seizures mixed in type. Seizures usually persist up to late childhood and are drug resistant. Further studies are necessary to better define the electroclinical patterns of patients carrying deletions in 2q24–q31. These may help to direct systematic study of this—probably underestimated—cause of severe epilepsy. [Copyright &y& Elsevier]

Abstract: We report a patient with mental retardation, epilepsy, overgrowth, delayed bone age, peculiar facial features, corpus callosum hypoplasia, enlarged cisterna magna and right cerebellar hypoplasia. Array-CGH analysis revealed the presence of a de novo 3.2 Mb interstitial deletion of the long arm of chromosome 7 involving bands q22.2–q22.3. The rearrangement includes 15 genes and encompasses a genomic region that represents a site of frequent loss of heterozygosity in myeloid malignancies. Four genes are implicated in the control of cell cycle: SRPK2, MLL5, RINT1 and LHFPL3. Haploinsufficiency of these genes might therefore be associated with overgrowth and could confer susceptibility to cancers or other tumours, so that attention to this possibility would be appropriate during regular medical review. In conclusion, array-CGH analysis should be performed in patients with overgrowth where the known causes have already been excluded, because some still unclassified overgrowth syndromes may be caused by subtle genomic imbalances. [Copyright &y& Elsevier]