GLUT-1DS resistant to ketogenic diet: from clinical feature to in silico analysis. An exemplificative case report with a literature review.

Glucose transporter type 1 deficiency syndrome (GLUT-1DS) is characterized by alterations in glucose translocation through the blood-brain barrier (BBB) due to mutation involving the GLUT-1 transporter. The fundamental therapy is ketogenic diet (KD) that provide an alternative energetic substrate - ketone bodies that across the BBB via MCT-1 - for the brain. Symptoms are various and include intractable seizure, acquired microcephalia, abnormal ocular movement, movement disorder, and neurodevelopment delay secondary to an energetic crisis for persistent neuroglycopenia. KD is extremely effective in controlling epileptic seizures and has a positive impact on movement disorders and cognitive impairment. Cases of KD resistance are rare, and only a few of them are reported in the literature, all regarding seizure. Our study describes a peculiar case of GLUT-1DS due to a new deletion involving the first codon of SLC2A1 gene determining a loss of function with a resistance to KD admitted to hospital due to intractable episodes of dystonia. This patient presented a worsening of symptomatology at higher ketonemia values but without hyperketosis and showed a complete resolution of symptomatology while maintaining low ketonemia values. Our study proposes an in-silico genomic and proteomic analysis aimed at explaining the atypical response to KD exhibited by our patient. In this way, we propose a new clinical and research approach based on precision medicine and molecular modelling to be applied to patients with GLUT-1DS resistant to first-line treatment with ketogenic diet by in silico study of genetic and altered protein product.

Severe Unilateral Microtia with Aural Atresia, Hair White Patch, Stereotypes in a Young Boy with De novo 16p13.11 Deletion: Reasons for a New Genotype-Phenotype Correlation.

Background Microtia is an uncommon congenital malformation ranging from mild anatomic structural abnormalities to partial or complete absence of the ear leading to hearing impairment. Congenital microtia may present as a single malformation (isolated microtia) or sometimes associated with other congenital anomalies involving various organs. Microtia has been classified in three degrees according to the complexity of the auricular malformation and to anotia referred to the total absence of the ear. Genetic role in causing auricular malformation has been widely demonstrated, and genotype-phenotype correlation has been reported in cases of syndromic microtia. Case Presentation We report here a young patient with a third degree of scale classification and aural atresia. The patient showed unspecific facial dysmorphism, speech delay, precocious teething, hair white patch, and stereotypic anomalous movements. Genetic analysis displayed a de novo 16p13.11 deletion. Conclusion Microtia with aural atresia is an uncommon and severe birth defect, which affects functional and esthetic aspects, often associated with other malformations. As traumatic this disorder may be for the parents, the microtia and aural atresia are treatable, thanks to the improving and evolving surgical techniques. Based on the genetic analysis and the clinical features observed in the present case, a genotype-phenotype correlation has been proposed.

Case report: Structural brain abnormalities in TUBA1A-tubulinopathies: a narrative review.

Introduction: Tubulin genes have been related to severe neurological complications and the term "tubulinopathy" now refers to a heterogeneous group of disorders involving an extensive family of tubulin genes with TUBA1A being the most common. A review was carried out on the complex and severe brain abnormalities associated with this genetic anomaly. Methods: A literature review of the cases of TUBA1A-tubulopathy was performed to investigate the molecular findings linked with cerebral anomalies and to describe the clinical and neuroradiological features related to this genetic disorder. Results: Clinical manifestations of TUBA1A-tubulinopathy patients are heterogeneous and severe ranging from craniofacial dysmorphism, notable developmental delay, and intellectual delay to early-onset seizures, neuroradiologically associated with complex abnormalities. TUBA1A-tubulinopathy may display various and complex cortical and subcortical malformations. Discussion: A range of clinical manifestations related to different cerebral structures involved may be observed in patients with TUBA1A-tubulinopathy. Genotype-phenotype correlations are discussed here. Individuals with cortical and subcortical anomalies should be screened also for pathogenic variants in TUBA1A.

A Young Boy with 21q21.1 Microdeletion Showing Speech Delay, Spastic Diplegia, and MRI Abnormalities: Original Case Report.

Chromosome 21q deletion syndrome is a rare disorder affecting the long arm of chromosome 21 and manifesting with wide phenotypic features depending on the size and position of the deleted region. In the syndrome, three distinct deleted regions have been distinguished: region 1, from the centromere to approximately 31.2 Mb (21q11.2-q22.11); region 2, from 31.2 to 36 Mb (21q22.11-q22.12); and region 3, from 36 to 37.5 Mb to the telomere (21q22.12-q22.3). The clinical features are highly variable manifesting with mild, poorly recognizable signs or with severe symptoms including craniofacial dysmorphism, growth failure, developmental delay, behavioral/affective abnormalities, and systemic malformations. We report here the case of a young boy with speech delay, mild spastic diplegia, and brain anomalies on magnetic resonance imaging (MRI). The genetic analysis displayed a microdeletion of the long arm of chromosome 21 approximately extending up to 1.08 Mb. Clinical presentation of the patient and cases of 21q21 deletion reported by the literature are discussed.

Human VDAC pseudogenes: an emerging role for VDAC1P8 pseudogene in acute myeloid leukemia.

BACKGROUND: Voltage-dependent anion selective channels (VDACs) are the most abundant mitochondrial outer membrane proteins, encoded in mammals by three genes, VDAC1, 2 and 3, mostly ubiquitously expressed. As 'mitochondrial gatekeepers', VDACs control organelle and cell metabolism and are involved in many diseases. Despite the presence of numerous VDAC pseudogenes in the human genome, their significance and possible role in VDAC protein expression has not yet been considered. RESULTS: We investigated the relevance of processed pseudogenes of human VDAC genes, both in physiological and in pathological contexts. Using high-throughput tools and querying many genomic and transcriptomic databases, we show that some VDAC pseudogenes are transcribed in specific tissues and pathological contexts. The obtained experimental data confirm an association of the VDAC1P8 pseudogene with acute myeloid leukemia (AML). CONCLUSIONS: Our in-silico comparative analysis between the VDAC1 gene and its VDAC1P8 pseudogene, together with experimental data produced in AML cellular models, indicate a specific over-expression of the VDAC1P8 pseudogene in AML, correlated with a downregulation of the parental VDAC1 gene.

Early Life Stress (ELS) Effects on Fetal and Adult Bone Development.

Early life stress (ELS) refers to harmful environmental events (i.e., poor maternal health, metabolic restraint, childhood trauma) occurring during the prenatal and/or postnatal period, which may cause the 'epigenetic corruption' of cellular and molecular signaling of mental and physical development. While the impact of ELS in a wide range of human diseases has been confirmed, the ELS susceptibility to bone diseases has been poorly explored. In this review, to understand the potential mediating pathways of ELS in bone diseases, PRISMA criteria were used to analyze different stress protocols in mammal models and the effects elicited in dams and their progeny. Data collected, despite the methodological heterogeneity, show that ELS interferes with fetal bone formation, also revealing that the stress type and affected developmental phase may influence the variety and severity of bone anomalies. Interestingly, these findings highlight the maternal and fetal ability to buffer stress, establishing a new role for the placenta in minimizing ELS perturbations. The functional link between ELS and bone impairments will boost future investigations on maternal stress transmission to the fetus and, parallelly, help the assessment of catch-up mechanisms of skeleton adaptations from the cascading ELS effects.

Diagnostic Tools in the Detection of Physical Child Abuse: A Systematic Review.

Child abuse is a critical social issue. The orthopedic surgeon's role is essential in noticing signs and symptoms of physical abuse. For this reason, several authors have proposed scoring systems to identify abuse early on and reduce undiagnosed cases. The aim of this systematic review is to overview the screening tools in the literature. In 2021, three independent authors performed a systematic review of two electronic medical databases using the following inclusion criteria: physical child abuse, questionnaire, survey, score, screening tool and predictive tool. Patients who had experienced sexual abuse or emotional abuse were excluded. The risk of bias evaluation of the articles was performed according to the Newcastle-Ottawa Quality Assessment Scale Cohort Studies. Any evidence-level study reporting clinical data and dealing with a physical child abuse diagnosis tool was considered. A total of 217 articles were found. After reading the full texts and checking the reference lists, n = 12 (71,035 patients) articles were selected. A total of seven screening tools were found. However, only some of the seven diagnostic tools included demonstrated a high rate of sensitivity and specificity. The main limits of the studies were the lack of heterogeneity of evidence and samples and the lack of common assessing tools. Despite the multiplicity of questionnaires aimed at detecting validated child abuse, there was not a single worldwide questionnaire for early diagnosis. A combination of more than one test might increase the validity of the investigation.

Alternating hemiplegia of childhood: a distinct clinical entity and ATP1A3-related disorders: A narrative review.

Alternating Hemiplegia of Childhood (AHC) is a rare disorder with onset in the first 18 months of life characterized by stereotyped paroxysmal manifestations of tonic and dystonic attacks, nystagmus with other oculomotor abnormalities, respiratory and autonomic dysfunctions. AHC is often associated with epileptic seizures and developmental delay. Hemiplegic paroxysm is the most remarkable symptom, although AHC includes a large series of clinical manifestations that interfere with the disease course. No cure is available and the treatment involves many specialists and therapies. Flunarizine is the most commonly used drug for reducing the frequency and intensity of paroxysmal events. Mutations in ATP1A2, particularly in ATP1A3, are the main genes responsible for AHC. Some disorders caused by ATP1A3 variants have been defined as ATP1A3-related disorders, including rapid-onset dystonia-parkinsonism, cerebellar ataxia, pes cavus, optic atrophy, sensorineural hearing loss, early infant epileptic encephalopathy, child rapid-onset ataxia, and relapsing encephalopathy with cerebellar ataxia. Recently, the term ATP1A3 syndrome has been identified as a fever-induced paroxysmal weakness and encephalopathy, slowly progressive cerebellar ataxia, childhood-onset schizophrenia/autistic spectrum disorder, paroxysmal dyskinesia, cerebral palsy/spastic paraparesis, dystonia, dysmorphism, encephalopathy, MRI abnormalities without hemiplegia, and congenital hydrocephalus. Herewith, we discussed about historical annotations of AHC, symptoms, signs and associated morbidities, diagnosis and differential diagnosis, treatment, prognosis, and genetics. We also reported on the ATP1A3-related disorders and ATP1A3 syndrome, as 2 recently established and expanded genetic clinical entities.

Pathogenic correlation between mosaic variegated aneuploidy 1 (MVA1) and a novel BUB1B variant: a reappraisal of a severe syndrome.

BACKGROUND: The BUB 1 mitotic checkpoint serine/threonine kinase B (BUB1B) gene encodes a key protein in the mitotic spindle checkpoint, which acts as a surveillance mechanism, crucial for the maintenance of the correct chromosome number during cell deviation. Mutations of BUB1B gene are linked to mosaic variegated aneuploidy 1 (MVA1) syndrome, a rare autosomal recessive disorder characterized by widespread mosaic aneuploidies, involving different chromosomes and tissues. MVA1 is clinically characterized by intrauterine growth restriction, post-natal growth retardation, and severe neurologic impairment including microcephaly, developmental delay/intellectual disability, epileptic seizures, and generalized hypotonia. Malignancies are also serious sequelae associated with the disorder. We reported on a case of two-year-old Italian girl with MVA1 who shows severe neurologic impairment, microcephaly and epileptic seizures. MATERIALS AND METHODS: Clinical data collection and genetic diagnosis of the patient were assessed. Mutational analysis covers the chromosomal microarray analysis, the gene methylation pattern studied using the methylation-specific multiplex ligation-dependent probe amplification, and the family-based Whole Exome Sequencing (WES). A literature research based on reported cases of MVA and premature chromatid separation was also included. RESULTS: Karyotyping has revealed 12% of mosaics in the patient who carries a novel variant in BUB1B gene (c.2679A > T, p.Arg893Ser) detected by WES. Thirty-one cases of MVA1 including the present report, and four prenatally diagnosed cases with MVA1 were selected and inspected. CONCLUSION: Clinical and genetic findings reported in the girl strongly suggest a new MVA1 genotype-phenotype correlation and lead to a reappraisal of a severe syndrome. Diagnosis and in-depth follow-up provided worthwhile data.

Fever-Associated Seizures or Epilepsy: An Overview of Old and Recent Literature Acquisitions.

In addition to central nervous system infections, seizures and fever may occur together in several neurological disorders. Formerly, based on the clinical features and prognostic evolution, the co-association of seizure and fever included classical febrile seizures (FS) divided into simple, complex, and prolonged FS (also called febrile status epilepticus). Later, this group of disorders has been progressively indicated, with a more inclusive term, as "fever-associated seizures or epilepsy" (FASE) that encompasses: (a) FS divided into simple, complex, and prolonged FS; (b) FS plus; (c) severe myoclonic epilepsy in infancy (Dravet syndrome); (d) genetic epilepsy with FS plus; and (e) febrile infection-related epilepsy syndrome (FIRES). Among the FASE disorders, simple FS, the most common and benign condition, is rarely associated with subsequent epileptic seizures. The correlation of FS with epilepsy and other neurological disorders is highly variable. The pathogenesis of FASE is unclear but immunological and genetic factors play a relevant role and the disorders belonging to the FASE group show to have an underlying common clinical, immunological, and genetic pathway. In this study, we have reviewed and analyzed the clinical data of each of the heterogeneous group of disorders belonging to FASE.

Alternating Hemiplegia of Childhood: neurological comorbidities and intrafamilial variability.

BACKGROUND: Alternating of Childhood (AHC) is an uncommon and complex disorder characterized by age of onset before 18 months with recurrent hemiplegia of one or either sides of the body or quadriplegia. The disorder is mainly caused by mutations in ATP1A3 gene, and to a lesser extent in ATP1A2 gene. In AHC neurological co-morbidities are various and frequently reported including developmental delay, epilepsy, tonic or dystonic spells, nystagmus,autonomic manifestations with intrafamilial variability. CASE PRESENTATION: Clinical and genetic findings of a couple of twins (Family 1: Case 1 and Case 2) and a couple of siblings (Family 2: Case 3 and Case 4) coming from two different Italian families affected by AHC were deeply examined. In twins of Family 1, a pathogenic variant in ATP1A3 gene (c.2318A>G) was detected. In siblings of Family 2, the younger brother showed a novel GRIN2A variant (c.3175 T > A), while the older carried the same GRIN2A variant, and two missense mutations in SCNIB (c.632 > A) and KCNQ2 (1870 G > A) genes. Clinical manifestations of the four affected children were reported along with cases of AHC drawn from the literature. CONCLUSIONS: Hemiplegic episode is only a sign even if the most remarkable of several and various neurological comorbidities in AHC affected individuals. Molecular analysis of the families here reported showed that clinical features of AHC may be also the result of an unexpected genetic heterogeneity.

A Novel 4q32.3 Deletion in a Child: Additional Signs and the Role of MARCH1.

The 4q deletion syndrome is an uncommon condition manifesting with broad clinical expression and phenotypic variability. We report a 5-year-old boy affected by 4q deletion syndrome who showed minor craniofacial features, growth failure, mild developmental delay, severe speech delay, and marked irascibility and aggressivity. Moreover, he showed precocious and crowded primary dentition, digital hyperlaxity, and congenital bilateral adducted thumbs, signs which were previously unreported in the syndrome. The array comparative genomic hybridization analysis revealed a 4q partial terminal deletion of ∼329.6 kb extending from 164.703.186 to 165.032.803 nt, which includes part of MARCH1 (membrane associated ring-CH-type finger 1) gene (OMIM#613331). Same rearrangement was found in his healthy mother. Clinical phenotype of the child and its relationship to the deleted region is presented with a revision of the cases having the same copy number losses from the literature and genomic variant databases.

VDAC Genes Expression and Regulation in Mammals.

VDACs are pore-forming proteins, coating the mitochondrial outer membrane, and playing the role of main regulators for metabolites exchange between cytosol and mitochondria. In mammals, three isoforms have evolutionary originated, VDAC1, VDAC2, and VDAC3. Despite similarity in sequence and structure, evidence suggests different biological roles in normal and pathological conditions for each isoform. We compared Homo sapiens and Mus musculus VDAC genes and their regulatory elements. RNA-seq transcriptome analysis shows that VDAC isoforms are expressed in human and mouse tissues at different levels with a predominance of VDAC1 and VDAC2 over VDAC3, with the exception of reproductive system. Numerous transcript variants for each isoform suggest specific context-dependent regulatory mechanisms. Analysis of VDAC core promoters has highlighted that, both in a human and a mouse, VDAC genes show features of TATA-less ones. The level of CG methylation of the human VDAC genes revealed that VDAC1 promoter is less methylated than other two isoforms. We found that expression of VDAC genes is mainly regulated by transcription factors involved in controlling cell growth, proliferation and differentiation, apoptosis, and bioenergetic metabolism. A non-canonical initiation site termed "the TCT/TOP motif," the target for translation regulation by the mTOR pathway, was identified in human VDAC2 and VDAC3 and in every murine VDACs promoter. In addition, specific TFBSs have been identified in each VDAC promoter, supporting the hypothesis that there is a partial functional divergence. These data corroborate our experimental results and reinforce the idea that gene regulation could be the key to understanding the evolutionary specialization of VDAC isoforms.

Losing DNA methylation at repetitive elements and breaking bad.

BACKGROUND: DNA methylation is an epigenetic chromatin mark that allows heterochromatin formation and gene silencing. It has a fundamental role in preserving genome stability (including chromosome stability) by controlling both gene expression and chromatin structure. Therefore, the onset of an incorrect pattern of DNA methylation is potentially dangerous for the cells. This is particularly important with respect to repetitive elements, which constitute the third of the human genome. MAIN BODY: Repetitive sequences are involved in several cell processes, however, due to their intrinsic nature, they can be a source of genome instability. Thus, most repetitive elements are usually methylated to maintain a heterochromatic, repressed state. Notably, there is increasing evidence showing that repetitive elements (satellites, long interspersed nuclear elements (LINEs), Alus) are frequently hypomethylated in various of human pathologies, from cancer to psychiatric disorders. Repetitive sequences' hypomethylation correlates with chromatin relaxation and unscheduled transcription. If these alterations are directly involved in human diseases aetiology and how, is still under investigation. CONCLUSIONS: Hypomethylation of different families of repetitive sequences is recurrent in many different human diseases, suggesting that the methylation status of these elements can be involved in preservation of human health. This provides a promising point of view towards the research of therapeutic strategies focused on specifically tuning DNA methylation of DNA repeats.

Intronic Variant in CNTNAP2 Gene in a Boy With Remarkable Conduct Disorder, Minor Facial Features, Mild Intellectual Disability, and Seizures.

Introduction: Mutations in the contactin-associated protein-like 2 (CNTNAP2) gene (MIM#604569) encoding for CASPR2, a cell adhesion protein of the neurexin family, are known to be associated with autism, intellectual disability, and other neuropsychiatric disorders. A set of intronic deletions of CNTNAP2 gene has also been suggested to have a causative role in individuals with a wide phenotypic spectrum, including Pitt-Hopkins syndrome, cortical dysplasia-focal epilepsy syndrome, Tourette syndrome, language dysfunction, and abnormal behavioral manifestations. Case presentation: A 10-years-old boy was referred to the hospital with mild intellectual disability and language impairment. Moreover, the child exhibited minor facial features, epileptic seizures, and notable behavioral abnormalities including impulsivity, aggressivity, and hyperactivity suggestive of the diagnosis of disruptive, impulse-control and conduct disorder (CD). Array comparative genomic hybridization (CGH) revealed a copy number variant (CNV) deletion in the first intron of CNTNAP2 gene inherited from a healthy father. Conclusions: A comprehensive description of the phenotypic features of the child is provided, revealing a distinct and remarkable alteration of social behavior not previously reported in individuals affected by disorders related to CNTNAP2 gene disruptions. A possible causative link between the deletion of a non-coding regulatory region and the symptoms presented by the boy has been advanced.

Is the secret of VDAC Isoforms in their gene regulation? Characterization of human VDAC genes expression profile, promoter activity, and transcriptional regulators.

VDACs (voltage-dependent anion-selective channels) are pore-forming proteins of the outer mitochondrial membrane, whose permeability is primarily due to VDACs' presence. In higher eukaryotes, three isoforms are raised during the evolution: they have the same exon-intron organization, and the proteins show the same channel-forming activity. We provide a comprehensive analysis of the three human VDAC genes (VDAC1-3), their expression profiles, promoter activity, and potential transcriptional regulators. VDAC isoforms are broadly but also specifically expressed in various human tissues at different levels, with a predominance of VDAC1 and VDAC2 over VDAC3. However, an RNA-seq cap analysis gene expression (CAGE) approach revealed a higher level of transcription activation of VDAC3 gene. We experimentally confirmed this information by reporter assay of VDACs promoter activity. Transcription factor binding sites (TFBSs) distribution in the promoters were investigated. The main regulators common to the three VDAC genes were identified as E2F-myc activator/cell cycle (E2FF), Nuclear respiratory factor 1 (NRF1), Krueppel-like transcription factors (KLFS), E-box binding factors (EBOX) transcription factor family members. All of them are involved in cell cycle and growth, proliferation, differentiation, apoptosis, and metabolism. More transcription factors specific for each VDAC gene isoform were identified, supporting the results in the literature, indicating a general role of VDAC1, as an actor of apoptosis for VDAC2, and the involvement in sex determination and development of VDAC3. For the first time, we propose a comparative analysis of human VDAC promoters to investigate their specific biological functions. Bioinformatics and experimental results confirm the essential role of the VDAC protein family in mitochondrial functionality. Moreover, insights about a specialized function and different regulation mechanisms arise for the three isoform gene.

A novel GABRB3 variant in Dravet syndrome: Case report and literature review.

BACKGROUND: Mutations in GABRB3 have been identified in subjects with different types of epilepsy and epileptic syndromes, including West syndrome (WS), Dravet syndrome (DS), Lennox-Gastaut syndrome (LGS), myoclonic-atonic epilepsy (MAE), and others. METHODS AND RESULTS: We herewith report on a girl affected by DS, who has been followed from infancy to the current age of 18 years. Next-generation sequencing (NGS)-based genetic testing for multigene analysis of neurodevelopmental disorders identified two likely de novo pathogenic mutations, a missense variant in GABRB3 gene (c.842 C>T; p.Thr281IIe) and a nonsense variant found in BBS4 gene (c.883 C>T; p.Arg295Ter). CONCLUSION: A likely relationship between the novel GABRB3 gene variant and the clinical manifestations presented by the girl is proposed. Previously, one case of DS and two of DS-like linked with GABRB3 mutations have been reported. To the best of our knowledge, this is the first report of DS associated with this novel variant. A literature review of clinical cases with various types of epileptic encephalopathies (EEs) related to GABRB3 mutations is reported.

NRF-1 and HIF-1α contribute to modulation of human VDAC1 gene promoter during starvation and hypoxia in HeLa cells.

VDAC (Voltage Dependent Anion Channel) is a family of pore forming protein located in the outer mitochondrial membrane. Its channel property ensures metabolites exchange between mitochondria and the rest of the cell resulting in metabolism and bioenergetics regulation, and in cell death and life switch. VDAC1 is the best characterized and most abundant isoform, and is involved in many pathologies, as cancer or neurodegenerative diseases. However, little information is available about its gene expression regulation in normal and/or pathological conditions. In this work, we explored VDAC1 gene expression regulation in normal conditions and in the contest of some metabolic and energetic mitochondrial dysfunction and cell stress as example. The core of the putative promoter region was characterized in terms of transcription factors responsive elements both by bioinformatic studies and promoter activity experiments. In particular, we found an abundant presence of NRF-1 sites, together with other transcription factors binding sites involved in cell growth, proliferation, development, and we studied their prevalence in gene activity. Furthermore, upon depletion of nutrients or controlled hypoxia, as detected in various pathologies, we found that VDAC1 transcripts levels were significantly increased in a time related manner. VDAC1 promoter activity was also validated by gene reporter assays. According to PCR real-time experiments, it was confirmed that VDAC1 promoter activity is further stimulated when cells are exposed to stress. A bioinformatic survey suggested HIF-1α, besides NRF-1, as a most active TFBS. Their validation was obtained by TFBS mutagenesis and TF overexpression experiments. In conclusion, we experimentally demonstrated the involvement of both NRF-1 and HIF-1α in the regulation of VDAC1 promoter activation at basal level and in some peculiar cell stress conditions.

Primary Microcephaly with Novel Variant of MCPH1 Gene in Twins: Both Manifesting in Childhood at the Same Time with Hashimoto's Thyroiditis.

This study is a clinical report on twin females affected by primary microcephaly who displayed at molecular analysis of heterozygous novel MCPH1 variant. The twins at the age of 10 years developed, in coincidental time, a diagnosis of autoimmune juvenile thyroiditis. The main clinical features presented by the twins consisted of primary microcephaly with occipitofrontal circumference measuring -2 or -3 standard deviation, facial dysmorphism, typical nonsyndromic microcephaly, and mild intellectual disability. Molecular analysis of the major genes involved in primary microcephaly was performed and the following result was found in the twins: MCPH1 ; chr8.6357416; c.2180 C > T (rs 199861426), p.Pro727. Leu; heterozygous; missense; variant of uncertain significance (class 3). At the age of 10 years, the twins started to have, in coincidental time, marked asthenia and episodes of emotiveness, and laboratory exams disclosed a high level of antithyroid peroxidase leading to the diagnosis of autoimmune juvenile thyroiditis with normal thyroid function. The novel heterozygous MCPH1 variant found in the twins may be directly or indirectly involved in the onset of the primary microcephaly. The thyroid disorder in the twins and its onset, in a coincidental time, confirmed the effect of genetic predisposition on the pathogenesis of the immune thyroiditis.

Long-term follow-up and novel genotype-phenotype analysis of monozygotic twins with ATP1A3 mutation in Alternating Hemiplegia of Childhood-2.

Alternating Hemiplegia of Childhood (AHC) is a rare disorder characterized by frequent, transient attacks of hemiplegia involving either side of the body or both in association to several other disturbances including dystonic spells, abnormal ocular movements, autonomic manifestations, epileptic seizures and cognitive impairment. The clinical manifestations usually start before the age of 18 months. Two forms of the disorder known as AHC-1 (MIM#104290) and AHC-2 (MIM#614820) depends on mutations in ATP1A2 and ATP1A3 genes respectively, with over 75% of AHC caused by a mutation in the ATP1A3 gene. Herewith, we report serial clinical follow-up data of monozygotic (MZ) twin sisters, who presented in early life bath-induced dystonia, signs of acute encephalopathy at the age of 2 years, hemiplegic spells, and motor dysfunction after the age of 3 years, and in young/adult frequent episodes of headache with drastic reduction of paroxysmal motor attacks. The molecular analysis revealed a known pathogenic variant p.Asn773Ser (rs606231437) in ATP1A3 gene associated with an unusual and moderate AHC-2 phenotype, with mild cognitive impairment and lack of epilepsy. The aim of this study is to analyze the clinical phases of the MZ twins, and to investigate the novel genotype-phenotype correlation.