scholarly journals Whole-exome sequencing in an individual with severe global developmental delay and intractable epilepsy identifies a novel, de novoGRIN2Amutation

Epilepsia ◽  
2014 ◽  
Vol 55 (7) ◽  
pp. e75-e79 ◽  
Author(s):  
Sunita Venkateswaran ◽  
Ken A. Myers ◽  
Amanda C. Smith ◽  
Chandree L. Beaulieu ◽  
Jeremy A. Schwartzentruber ◽  
...  
Gene ◽  
2018 ◽  
Vol 673 ◽  
pp. 56-60 ◽  
Author(s):  
Venugopal S. Vineeth ◽  
Usha R. Dutta ◽  
Karthik Tallapaka ◽  
Aneek Das Bhowmik ◽  
Ashwin Dalal

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Alyssa M Dye ◽  
Grace Bazan Nelson ◽  
Alicia Marie Diaz-Thomas

Abstract Background: Allan-Herndon-Dudley (AHD) is a rare X-linked disorder with neurological manifestations secondary to a mutation in monocarboxylate transporter 8, a protein that transports T3 into nerve cells in the brain. AHD is characterized by increased serum free T3, decreased serum free T4 and normal serum TSH levels as well as the severe neurological manifestations including global developmental delay, hypotonia, and joint contractures (1). A phase 2 trial using triodyothyroacetic acid has shown promise in treating this disorder (2). We report on three children who were diagnosed by whole exome sequencing after presenting with neurological manifestations. Clinical Cases: Patient 1 presented at 4 months to the neurology clinic for seizures. He had a normal newborn screen. Worsening developmental delays and central hypotonia prompted a brain MRI that revealed delayed myelination for age. At 6 months a chromosomal microarray and metabolic work-up were performed and were nondiagnostic. Whole exome sequencing was obtained at the age of 4.5 years revealing a mutation in the SLC16A2 gene (p.Ser210Tyr). Thyroid studies were consistent with the diagnosis. Patient 2 presented to neurology at 9 months for developmental delay. A brain MRI was obtained which was within normal limits. At 14 months an acylcarnitine profile was obtained which indicated a possible CPT1 deficiency, which did not fit his clinical picture. Chromosomal microarray as well as work-up for inborn errors of metabolism were performed and were nondiagnostic. Thyroid studies were obtained which showed low free T4 with normal TSH. Whole exome sequencing was obtained at the age of 2.5 years, which revealed a mutation in SLC16A2 (p.R371C). Patient 3 presented as sibling of patient 2 with known AHD syndrome. Testing for SLC16A2 was performed at the age of 5 months and returned positive for same mutation as sibling (p.R371C). Conclusion: Allan-Herndon-Dudley syndrome is a rare neurological disease secondary to a mutation in the T3 transporter protein to nervous tissue. A high index of suspicion as well as thyroid studies should be obtained in patients presenting with central hypotonia and global developmental delay with normal newborn screens, particularly in states that use TSH as a screening test. This is especially important as treatments are becoming available that may help prevent neurological devastation seen in these patients. References: 1. Dumitrescu AM, Fu J, Dempsey MA, Refetoff S. MCT8-Specific Thyroid Hormone Cell-Membrane Transporter Deficiency. In: Adam MP, Ardinger HH, Pagon RA, et al., eds. GeneReviews®. Seattle (WA): University of Washington, Seattle; 1993 2. Groeneweg S, Peeters RP, Moran C, et al. Effectiveness and safety of the tri-iodothyronine analogue Triac in children and adults with MCT8 deficiency: an international, single-arm, open-label, phase 2 trial. Lancet Diabetes Endocrinol. 2019;7(9):695-706.


Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 229
Author(s):  
Pietro Palumbo ◽  
Ester Di Muro ◽  
Maria Accadia ◽  
Mario Benvenuto ◽  
Marilena Carmela Di Giacomo ◽  
...  

Neurodevelopmental disorders (NDDs) are a group of highly prevalent, clinically and genetically heterogeneous pediatric disorders comprising, according to the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-V), intellectual disability, developmental delay, autism spectrum disorders, and other neurological and cognitive disorders manifesting in the developmental age. To date, more than 1000 genes have been implicated in the etiopathogenesis of NNDs. Among them, AUTS2 (OMIM # 607270) encodes a protein involved in neural migration and neuritogenesis, and causes NNDs with different molecular mechanisms including copy number variations, single or multiple exonic deletion and single nucleotide variants. We describes a 9-year-old boy with global developmental delay, absent speech, minor craniofacial anomalies, hypoplasia of the cerebellar vermis and thinning of the corpus callosum, resulted carrier of the de novo AUTS2 c.1603_1626del deletion at whole exome sequencing (WES) predicted to cause the loss of eight amino acids [p.(His535_Thr542del)]. Notably, our patient is the first reported so far in medical literature carrying an in-frame deletion and the first in which absent language, hypoplasia of the cerebellar vermis and thinning of the corpus callosum has been observed thus useful to expand the molecular spectrum of AUTS2 pathogenic variants and to broaden our knowledge on the clinical phenotype associated.


2020 ◽  
Author(s):  
Soo Yeon Kim ◽  
YoungKyu Shim ◽  
Young Joon Ko ◽  
Soojin Park ◽  
Se Song Jang ◽  
...  

Abstract Background GNAO1 encephalopathy is a rare neurodevelopmental disorder characterized by distinct movement presentations and early onset epileptic encephalopathy. Here, we report the in-depth phenotyping of genetically confirmed patients with GNAO1 encephalopathy, focusing on movement presentations. Results Six patients who participated in Korean Undiagnosed Disease Program were diagnosed to have pathogenic or likely pathogenic variants in GNAO1 using whole exome sequencing. All medical records and personal video clips were analyzed with a literature review. Three of the 6 patients were male. Mean follow-up duration was 39 months (range, 7–78 months) and age at last examination was 8.0 years (range, 3.3–16.9 years). Initial complaints were hypotonia or developmental delay in 5 and right-hand clumsiness in 1 patient, which were noticed at 20 months of age on average (range, 0–75 months). All patients showed global developmental delay and 4 had severely retarded development. Five patients (5/6, 83.3%) had many different movement symptoms with various onset and progression. The symptoms included stereotyped hands movement, non-epileptic myoclonus, dyskinesia, dystonia and choreoathetosis. Whole exome sequencing identified 6 different variants in GNAO1. Three were novel de novo variants and atypical presentation was noted in a patient. One variant turned out to be inherited from patient’s mother who had mosaic variant. Distinct phenotypes in patients with variant p.Glu246Lys and p.Arg209His were elucidated by in-depth phenotyping and literature review. Conclusions We reported 6 patients with GNAO1 encephalopathy showing an extremely diverse clinical spectrum on video. Some characteristic movement features identified by careful inspection may also provide important diagnostic insight and practice guidelines.


2020 ◽  
Author(s):  
Soo Yeon Kim ◽  
YoungKyu Shim ◽  
Young Joon Ko ◽  
Soojin Park ◽  
Se Song Jang ◽  
...  

Abstract Background: GNAO1 encephalopathy is a rare neurodevelopmental disorder characterized by distinct movement presentations and early onset epileptic encephalopathy. Here, we report the in-depth phenotyping of genetically confirmed patients with GNAO1 encephalopathy, focusing on movement presentations.Results: Six patients who participated in Korean Undiagnosed Disease Program were diagnosed to have pathogenic or likely pathogenic variants in GNAO1 using whole exome sequencing. All medical records and personal video clips were analyzed with a literature review. Three of the 6 patients were male. Median follow-up duration was 41 months (range, 7–78 months) and age at last examination was 7.4 years (range, 3.3–16.9 years). Initial complaints were hypotonia or developmental delay in 5 and right-hand clumsiness in 1 patient, which were noticed at median age of 3 months (range, 0–75 months). All patients showed global developmental delay and 4 had severely retarded development. Five patients (5/6, 83.3%) had many different movement symptoms with various onset and progression. The symptoms included stereotyped hands movement, non-epileptic myoclonus, dyskinesia, dystonia and choreoathetosis. Whole exome sequencing identified 6 different variants in GNAO1. Three were novel de novo variants and atypical presentation was noted in a patient. One variant turned out to be inherited from patient’s mother who had mosaic variant. Distinct and characteristics movement phenotypes in patients with variant p.Glu246Lys and p.Arg209His were elucidated by in-depth phenotyping and literature review. Conclusions: We reported 6 patients with GNAO1 encephalopathy showing an extremely diverse clinical spectrum on video. Some characteristic movement features identified by careful inspection may also provide important diagnostic insight and practice guidelines.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Soo Yeon Kim ◽  
YoungKyu Shim ◽  
Young Joon Ko ◽  
Soojin Park ◽  
Se Song Jang ◽  
...  

Abstract Background GNAO1 encephalopathy is a rare neurodevelopmental disorder characterized by distinct movement presentations and early onset epileptic encephalopathy. Here, we report the in-depth phenotyping of genetically confirmed patients with GNAO1 encephalopathy, focusing on movement presentations. Results Six patients who participated in Korean Undiagnosed Disease Program were diagnosed to have pathogenic or likely pathogenic variants in GNAO1 using whole exome sequencing. All medical records and personal video clips were analyzed with a literature review. Three of the 6 patients were male. Median follow-up duration was 41 months (range 7–78 months) and age at last examination was 7.4 years (range 3.3–16.9 years). Initial complaints were hypotonia or developmental delay in 5 and right-hand clumsiness in 1 patient, which were noticed at median age of 3 months (range 0–75 months). All patients showed global developmental delay and 4 had severely retarded development. Five patients (5/6, 83.3%) had many different movement symptoms with various onset and progression. The symptoms included stereotyped hands movement, non-epileptic myoclonus, dyskinesia, dystonia and choreoathetosis. Whole exome sequencing identified 6 different variants in GNAO1. Three were novel de novo variants and atypical presentation was noted in a patient. One variant turned out to be inherited from patient’s mother who had mosaic variant. Distinct and characteristics movement phenotypes in patients with variant p.Glu246Lys and p.Arg209His were elucidated by in-depth phenotyping and literature review. Conclusions We reported 6 patients with GNAO1 encephalopathy showing an extremely diverse clinical spectrum on video. Some characteristic movement features identified by careful inspection may also provide important diagnostic insight and practice guidelines.


2018 ◽  
Vol 55 (12) ◽  
pp. 847-852 ◽  
Author(s):  
Kit San Yeung ◽  
Matthew Sai Pong Ho ◽  
So Lun Lee ◽  
Anita Sik Yau Kan ◽  
Kelvin Yuen Kwong Chan ◽  
...  

BackgroundWe report here clinical, cytogenetic and molecular data for a pair of monochorionic diamniotic twins with paternal isodisomy for chromosome 19. Both twins presented with dysmorphic features and global developmental delay. This represents, to our knowledge, the first individual human case of paternal uniparental disomy for chromosome 19 (UPD19).MethodsWhole-exome sequencing, together with conventional karyotype and SNP array analysis were performed along with genome-wide DNA methylation array for delineation of the underlying molecular defects.ResultsConventional karyotyping on amniocytes and lymphocytes showed normal karyotypes for both twins. Whole-exome sequencing did not identify any pathogenic sequence variants but >5000 homozygous exonic variants on chromosome 19, suggestive of UPD19. SNP arrays on blood and buccal DNA both showed paternal isodisomy for chromosome 19. Losses of imprinting for known imprinted genes on chromosome 19 were identified, including ZNF331, PEG3, ZIM2 and MIMT1. In addition, imprinting defects were also identified in genes located on other chromosomes, including GPR1-AS, JAKMP1 and NHP2L1.ConclusionImprinting defects are the most likely cause for the dysmorphism and developmental delay in this first report of monozygotic twins with UPD19. However, epigenotype-phenotype correlation will require identification of additional individuals with UPD19 and further molecular analysis.


Author(s):  
Amira Masri ◽  
Hanan Hamamy

AbstractThis retrospective study was aiming to determine the cost effectiveness of whole exome sequencing (WES) in the diagnosis of children with developmental delay in a developing country. In this study of 40 patients, the average cost of traditional investigations and indirect costs related to rehabilitation and medications per child were USD847 and 6,585 per year, respectively. With a current cost for WES of approximately USD1,200, we concluded that performing WES could be cost effective, even in countries with limited resources, as it provides the option for genetic counseling in affected families with an ultimate reduction of overall financial burden to both parents and health care system.


2020 ◽  
Vol 9 (11) ◽  
pp. 3724
Author(s):  
Min-Jee Kim ◽  
Mi-Sun Yum ◽  
Go Hun Seo ◽  
Yena Lee ◽  
Han Na Jang ◽  
...  

Background: The aim of this study was to describe the application of whole exome sequencing (WES) in the accurate genetic diagnosis and personalized treatment of extremely rare neurogenetic disorders. Methods: From 2017 to 2019, children with neurodevelopmental symptoms were evaluated using WES in the pediatric neurology clinic and medical genetics center. The clinical presentation, laboratory findings including the genetic results from WES, and diagnosis-based treatment and outcomes of the four patients are discussed. Results: A total of 376 children with neurodevelopmental symptom were evaluated by WES, and four patients (1.1%) were diagnosed with treatable neurologic disorders. Patient 1 (Pt 1) showed global muscle hypotonia, dysmorphic facial features, and multiple anomalies beginning in the perinatal period. Pt 1 was diagnosed with congenital myasthenic syndrome 22 of PREPL deficiency. Pt 2 presented with hypotonia and developmental arrest and was diagnosed with autosomal recessive dopa-responsive dystonia due to TH deficiency. Pt 3, who suffered from intractable epilepsy and progressive cognitive decline, was diagnosed with epileptic encephalopathy 47 with a heterozygous FGF12 mutation. Pt 4 presented with motor delay and episodic ataxia and was diagnosed with episodic ataxia type II (heterozygous CACNA1A mutation). The patients’ major neurologic symptoms were remarkably relieved with pyridostigmine (Pt 1), levodopa (Pt 2), sodium channel blocker (Pt 3), and acetazolamide (Pt 4), and most patients regained developmental milestones in the follow-up period (0.4 to 3 years). Conclusions: The early application of WES helps in the identification of extremely rare genetic diseases, for which effective treatment modalities exist. Ultimately, WES resulted in optimal clinical outcomes of affected patients.


2021 ◽  
Vol 12 ◽  
Author(s):  
Bingbo Zhou ◽  
Chuan Zhang ◽  
Lei Zheng ◽  
Zhiqiang Wang ◽  
Xue Chen ◽  
...  

Introduction: Neurodevelopmental disorders with language impairment and behavioral abnormalities (NEDLIB) are a disease caused by heterozygous variants in the glutamate ionotropic receptor AMPA type subunit 2 (GRIA2) gene, which manifest as impaired mental development or developmental delay, behavioral abnormalities including autistic characteristics, and language disorders. Currently, only a few mutations in the GRIA2 gene have been discovered.Methods: A GRIA2 variation was detected in a patient by whole-exome sequencing, and the site was validated by Sanger sequencing from the family.Results: We report a Chinese case of NEDLIB in a girl with language impairment and developmental delay through whole-exome sequencing (WES). Genetic analysis showed that there was a de novo missense mutation, c.1934T > G (p.Leu645Arg), in the GRIA2 gene (NM_001083619.1), which has never been reported before.Conclusion: Our case shows the potential diagnostic role of WES in NEDLIB, expands the GRIA2 gene mutation spectrum, and further deepens the understanding of NEDLIB. Deepening the study of the genetic and clinical heterogeneity, treatment, and prognosis of the disease is still our future challenge and focus.


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