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PURPOSE: We aimed to define a novel autosomal recessive neurodevelopmental disorder, characterize its clinical features, and identify the underlying genetic cause for this condition. METHODS: We performed a detailed clinical characterization of 19 individuals from nine unrelated, consanguineous families with a neurodevelopmental disorder. We used genome/exome sequencing approaches, linkage and cosegregation analyses to identify disease-causing variants, and we performed three-dimensional molecular in silico analysis to predict causality of variants where applicable. RESULTS: In all affected individuals who presented with a neurodevelopmental syndrome with progressive microcephaly, seizures, and intellectual disability we identified biallelic disease-causing variants in Protocadherin-gamma-C4 (PCDHGC4). Five variants were predicted to induce premature protein truncation leading to a loss of PCDHGC4 function. The three detected missense variants were located in extracellular cadherin (EC) domains EC5 and EC6 of PCDHGC4, and in silico analysis of the affected residues showed that two of these substitutions were predicted to influence the Ca2+-binding affinity, which is essential for multimerization of the protein, whereas the third missense variant directly influenced the cis-dimerization interface of PCDHGC4. CONCLUSION: We show that biallelic variants in PCDHGC4 are causing a novel autosomal recessive neurodevelopmental disorder and link PCDHGC4 as a member of the clustered PCDH family to a Mendelian disorder in humans.

Developmental and Epileptic Encephalopathies are a heterogeneous group of early-onset epilepsy syndromes dramatically impairing neurodevelopment. Modern genomic technologies have revealed a number of monogenic origins and opened the door to therapeutic hopes. Here we describe a new syndromic developmental and epileptic encephalopathies caused by bi-allelic loss of function variants in GAD1, as presented by eleven patients from 6 independent consanguineous families. Seizure onset occurred in the two first months of life in all patients. All 10 patients from whom early disease history was available, presented seizure onset in the first month of life, mainly consisting of epileptic spasms or myoclonic seizures. Early electroencephalography showed suppression-burst or pattern of burst attenuation or hypsarrhythmia if only recorded in the post-neonatal period. Eight patients had joint contractures and/or pes equinovarus. Seven patients presented a cleft palate and two also had an omphalocele, reproducing the phenotype of the knockout Gad1-/- mouse model. Four patients died before four years of age. GAD1 encodes the glutamate decarboxylase enzyme GAD67, a critical actor of the γ-aminobutyric acid (GABA) metabolism as it catalyzes the decarboxylation of glutamic acid to form GABA. Our findings evoke a novel syndrome related to GAD67 deficiency, characterized by the unique association of developmental and epileptic encephalopathies, cleft palate, joint contractures and/or omphalocele.

Zollo et al. report that mutations in PRUNE1, a phosphoesterase superfamily molecule, underlie primary microcephaly and profound global developmental delay in four unrelated families from Oman, India, Iran and Italy. The study highlights a potential role for prune during microtubule polymerization, suggesting that prune syndrome may be a tubulinopathy., PRUNE is a member of the DHH (Asp-His-His) phosphoesterase protein superfamily of molecules important for cell motility, and implicated in cancer progression. Here we investigated multiple families from Oman, India, Iran and Italy with individuals affected by a new autosomal recessive neurodevelopmental and degenerative disorder in which the cardinal features include primary microcephaly and profound global developmental delay. Our genetic studies identified biallelic mutations of PRUNE1 as responsible. Our functional assays of disease-associated variant alleles revealed impaired microtubule polymerization, as well as cell migration and proliferation properties, of mutant PRUNE. Additionally, our studies also highlight a potential new role for PRUNE during microtubule polymerization, which is essential for the cytoskeletal rearrangements that occur during cellular division and proliferation. Together these studies define PRUNE as a molecule fundamental for normal human cortical development and define cellular and clinical consequences associated with PRUNE mutation.

Objective Homocystinuria is an inborn error of amino acid metabolism caused by cystathionine beta-synthase deficiency that affects methionine metabolism. The clinical features are heterogeneous ranging from mental retardation, ectopia lentis, and osteoporosis to vascular events such as deep vein thrombosis, sagital sinus thrombosis, and myocardial infarction. Cerebral sinovenous thrombosis (CVST) is an unusual disorder in children and requires prompt and accurate management. Some causal factors for the development of CVST differ between children and adults. The majority of cases with CSVT are found to have an underlying cause for thrombosis like dehydration, infections, prothrombotic and hematologic disorders, malignancy and trauma. Although homocystinuria is usually associated with ischemic strokes, CVST as initial clinical presentation of homocystinuria is rare in children. In this article, we presented a 10-year old boy with seizure, hemiparesis, and ataxia due to CSVT caused by homocystinuria.

Joubert syndrome (JS) is a rare autosomal recessive central nervous system malformation characterized by hypoplasia of the cerebellar vermis, hypotonia and abnormal psychomotor development, along with altered respiratory pattern and various ophthalmologic features. Here, we describe three children with Joubert syndrome in a family that had almost similar presentations, including ataxia, developmental delay, mental retardation and ocular disorders. Prevalence of Joubert syndrome is about 1 in 100,000 live birth. It may be accompanied by other organs’ disorders. The molar tooth sign is pathognomonic for joubert syndrome that is ascertained by brain MRI.

BACKGROUND AND OBJECTIVE: Hyperbilirubinemia is one of the most common problems during the neonatal period. Despite the severe complications of jaundice, no reliable data is available regarding the prevalence of acute and chronic complications of jaundice and the predisposing factors in our community. Therefore, this study aimed to determine the complications of neonatal jaundice and the predisposing factors in neonates. METHODS: This cross-sectional study was performed on icteric, term newborns with bilirubin level higher than 20 mg/dl, referring to Ghaem Hospital during 2003-2013. After history taking and physical examinations, developmental status of infants was followed within six and twelve months after birth, using Denver Developmental Screening Test-II. The newborns were divided into two groups, based on the occurrence or non-occurrence of complications (e.g., acute or chronic kernicterus, auditory disorders and developmental disorders). Afterwards, predisposing factors for these complications were evaluated. FINDINGS Complications of jaundice were reported in 143 (13.37%) out of 1069 neonates. The two groups were not significantly different in terms of variables such as neonatal age and gender or maternal age. However, there was a significant difference between the children with and withod complication regarding treatment modality and mean total serum bilirubin level (27 mg/dl vs. 32 mg/dl) (p

Many neurologic manifestations of Epstein-Barr virus (EBV) infection have been documented, including encephalitis, aseptic meningitis, transverse myelitis, and Guillain-Barre syndrome. These manifestations can occur alone or coincidentally with the clinical picture of infectious mononucleosis. EBV encephalitis is rare and is indicated as a wide range of clinical manifestations. We report a 10-year-old girl presented with fever, gait disturbance, and bizarre behavior for one week. The results of the physical examination were unremarkable. The diagnosis of EBV encephalitis was made by changes in titers of EBV specific antibodies and MRI findings. A cranial MRI demonstrated abnormal high signal intensities in the basal ganglia and the striatal body, especially in the putamen and caudate nucleus. EBV infection should be considered when lesions are localized to the basal ganglia.

Objective Kearns-Sayre syndrome is a mitochondrial myopathy, which was first described by Tomas Kearn in 1958. Diagnostic symptoms include retinitis pigmentosa, chronic and progressive external ophthalmoplegia plus one or more of following factors: heart conduction system disorders, cerebellar ataxia, or cerebrospinal fluid (CSF) protein content above 100 mg/dL. The nature of this uncommon disease is yet to be clarified. In this paper, we report a case of Kearns-Sayre syndrome. According to the previous records, the first manifestation of Kearns- Sayre syndrome as hypoparathyroidism is uncommon and in this article, we report a case with this problem.

Objective Angelman syndrome (AS) is a neurodevelopmental disorder presented by jerky movement, speech delay and cognitive disability epilepsy as well as dysmorphic features. It occurs due to an expression deletion in 15q11-q13 chromosome. In this article, we present an eight yr boy referred to Pediatrics Neurologic Clinic Mashhad, Iran for speech delay. He had abnormal behavior ataxia unusual laughing facial expression intellectual disability and mandibular prognathism. Metabolic screening tests and brain MRI were normal. Genetic analysis was pathognomonic for AS.