scholarly journals Whole exome sequencing reveals a MLL de novo mutation associated with mild developmental delay and without ‘hairy elbows’: expanding the phenotype of Wiedemann–Steiner syndrome

2015 ◽  
Vol 94 (4) ◽  
pp. 755-758 ◽  
Author(s):  
DORA STEEL ◽  
VINCENZO SALPIETRO ◽  
RAHUL PHADKE ◽  
MATTHEW PITT ◽  
GIULIA GENTILE ◽  
...  
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.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2892-2892 ◽  
Author(s):  
Cecile Bally ◽  
Jacqueline Lehmann-Che ◽  
Bruno Cassinat ◽  
Lionel Ades ◽  
Eric Letouze ◽  
...  

Abstract Background : APL is, in the vast majority of cases, driven by t(15 ;17) translocation, which leads to PML/RARA rearrangement. Remarkably, APL is an uncommon genetically simple disease and only few additional alterations, cooperating with PML/RAR, have been described at diagnostic (Welch et al, Cell 2012). Most APL can be cured with targeted therapy combining all-trans retinoic acid (ATRA) and chemotherapy (CT). However, genetic mechanisms underlying the 10-15% relapses observed with this regimen remain unclear. The goal of the present study was to identify mutations that cooperate with PML/RAR and those responsible for acquired resistance to ATRA-CT treatment in APL patients by whole-exome sequencing of diagnostic/ remission/relapse trios. Methods: Newly diagnosed APL patients included in clinical trials of the French Swiss Belgian APL group between 1994 and 2008, treated with ATRA-CT, before the introduction of first-line ATO, who experienced at least one relapse and had adequate material, were studied. We collected retrospectively 64 samples from 23 patients, including 23 diagnostic samples, 18 at first complete remission (CR) and 23 at relapse (22 first relapse and 1 second relapse). Whole exome-sequencing was performed on all samples. DNA libraries were prepared with the SureSelect human v5 kit (Agilent) and sequenced on Hiseq1000 (Illumina). The bioinformatic analysis was performed by GECO/integragen using CASAVA variant calling (Illumina) and dedicated pipeline. 18 trios and 5 duos passed the stringent quality control and were analyzed for somatic variants and copy number variations (CNV). Results : After elimination of polymorphisms, the median number of somatic variants corresponding to de novo mutation at diagnosis was 14, while only 3 new somatic variants appeared at relapse (figure 1). Notably, we failed to detect oncogene alterations other than PML/RARA in 7/23 (30%) patients. At diagnostic, 39% of patients (9/23) presented the common FLT3 alterations and at relapse 22% (5/23) of patients presented the known RARA mutations. Moreover, recurrent alterations were observed in activators of the MAPK signaling (22%): NRAS (2 patients), BRAF (1 patient), KRAS (1 patient), SPRY1 (1 patient). Mutations in the NT5C2 gene (3 patients), coding a 5'nucleotidase implicated in resistance to nucleoside-analog therapy, were solely observed at relapse, as in acute lymphoblastic leukemia (ALL). Abnormalities of epigenetic regulators were also detected at diagnostic and/or relapse: WT1 (7 patients, 30%), NSD1 (2 patients), TET2 (1 patient), ASXL1 (1 patient) and MED12 (2 patients). Homozygote WT1 inactivation by mutation plus neutral copy LOH occurred in 3 patients at relapse. The genetic markers identified allowed us to construct several evolution models. In 8 patients (35%), the diagnostic and relapse clones were clearly distinct, supporting the fact that they independently derived from pre-leukemic cells that survived ATRA/chemotherapy. In contrast, other relapses appeared to derive from the diagnostic clone. Conclusion: Our data highlight the genetic simplicity of APL with very few alterations detected and 30% patients without identified mutations in addition to PML/RARa. Our results support the existence of two prototypic mechanisms of relapse: re-emergence of a new APL from persisting pre-leukemic cells and relapse from APLs often expressing strong oncogenes at diagnosis, impeding therapy response and favoring the acquisition of resistance mutations at relapse, including PML/RARA or NT5C2. It will be interesting to assess the prevalence of those two mechanisms in the exceptional cases of relapse in patients treated with more recent frontline regimens that combine ATRA and arsenic in APL. Disclosures Ades: Celgene, Takeda, Novartis, Astex: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Fenaux:Celgene, Janssen,Novartis, Astex, Teva: Honoraria, Research Funding.


2015 ◽  
Vol 9 (1) ◽  
Author(s):  
Katre Maasalu ◽  
Tiit Nikopensius ◽  
Sulev Kõks ◽  
Margit Nõukas ◽  
Mart Kals ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Jing Chen ◽  
Zhongmin Xia ◽  
Yulin Zhou ◽  
Xiaomin Ma ◽  
Xudong Wang ◽  
...  

Abstract Background KBG syndrome is a rare autosomal dominant genetic disease mainly caused by pathogenic variants of ankyrin repeat domain-containing protein 11 (ANKRD11) or deletions involving ANKRD11. Herein, we report a novel de novo heterozygous frameshift ANKRD11 variant via whole exome sequencing in a Chinese girl with KBG syndrome. Case presentation A 2-year-2-month-old girl presented with a short stature and developmental delay. Comprehensive physical examinations, endocrine laboratory tests and imaging examination were performed. Whole‐exome sequencing and Sanger sequencing were used to detect and confirm the variant associated with KBG in this patient, respectively. The pathogenicity of the variant was further predicted by several in silico prediction tools. The patient was diagnosed as KBG syndrome with a short stature and developmental delay, as well as characteristic craniofacial abnormalities, including a triangular face, long philtrum, wide eyebrows, a broad nasal bridge, prominent and protruding ears, macrodontia of the upper central incisors, dental crowding, and binocular refractive error. Her skeletal anomalies included brachydactyly, fifth finger clinodactyly, and left-skewed caudal vertebrae. Electroencephalographic results generally showed normal background activity with sporadic spikes and slow wave complexes, as well as multiple spikes and slow wave complexes in the bilateral parietal, occipital, and posterior temporal regions during non-rapid-eye-movement sleep. Brain MRI showed a distended change in the bilateral ventricles and third ventricle, as well as malformation of the sixth ventricle. Whole exome sequencing revealed a novel heterozygous frameshift variant in the patient, ANKRD11 c.1366_1367dup, which was predicted to be pathogenic through in silico analysis. The patient had received physical therapy since 4 months of age, and improvement of gross motor dysfunction was evident. Conclusions The results of this study expand the spectrum of ANKRD11 variants in KBG patients and provide clinical phenotypic data for KBG syndrome at an early age. Our study also demonstrates that whole exome sequencing is an effective method for the diagnosis of rare genetic disorders.


2021 ◽  
Vol 19 (2) ◽  
pp. 223-228
Author(s):  
Ma Thi Huyen Thuong ◽  
Dang Tien Truong ◽  
Nguyen Hai Ha ◽  
Nguyen Dang Ton

Epidermolysis bullosa simplex (EBS) is a group of epidermolysis bullosa (EB) and accounts for 75-85% EB cases. Most EBS patients are caused by mutations in KRT5 or KRT14, encoding for keratin 5 and keratin 14, respectively, which impair the structural entirety of paired intermediate filaments expressed in the fracture of basal keratinocytes and subsequent blistering of the epithelium. This study aimed to identify the causative mutation in a Vietnamese EB case. Whole exome sequencing (WES) was performed in the affected individual and revealed a de novo heterozygous pathogenic mutation in exon 7 of KRT5 gene, resulting in an amino acid change at position 477, with glutamic acid to lysine substitution (p.E477K). The KRT5 p.E477K was strong associated with the very severe or lethal of generalized severe EBS (GS-EBS), characterized by the severe symptoms at birth, improving with age and evolution to palmoplantar keratoderma and nail dysplasia. Our finding will aid the molecular diagnosis, prognosis prediction of the patient with GS-EBS due to p.E477K and significant genetic counselling the family concerning the recurrence risk for future pregnancies.


2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Lv Liu ◽  
Chan Chen ◽  
YaLi Li ◽  
Rong Yu

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare and potentially life-threatening disorder of the heart. The clinical spectrum of ARVC includes myocyte loss and fibro-fatty tissue replacement. With the progress of ARVC, the patient can present serious ventricular arrhythmias, heart failure, and even sudden cardiac death. Previous studies have demonstrated that desmosomes and intermediate junctions play a crucial role in the generation and development of ARVC. In this study, we enrolled a Chinese patient with suspicious ARVC. The patient suffered from right ventricular enlargement and less thickening of right ventricular wall. ECG record showed an epsilon wave. However, there was no obvious symptom in his parents. After whole-exome sequencing and data filtering, we identified a de novo mutation (c.1729C>T/p.R577C) of junction plakoglobin (JUP) in this patient. Bioinformatics programs predicted that this mutation was deleterious. Western blot revealed that, compared to cells transfected with WT plasmids, the expressions of desmoglein 2 (DSG2) and Connexin 43 were decreased overtly in cells transfected with the mutant plasmid. Previous studies have proven that the reduction of DSG2 and Connexin 43 may disturb the stability of desmosomes. In this research, we reported a novel de novo mutation (c.1729C>T/p.R577C) of JUP in a Chinese patient with suspicious ARVC. Functional research further confirmed the pathogenicity of this novel mutation. Our study expanded the spectrum of JUP mutations and may contribute to the genetic diagnosis and counseling of patients with ARVC.


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 ◽  
Vol 18 (2) ◽  
pp. 209-221
Author(s):  
Ngoc-Lan Nguyen ◽  
Ngoc Khanh Nguyen ◽  
Chi Dung Vu ◽  
Nguyen Thi Thu Huong ◽  
Nguyen Huy Hoang

            Our report describes a female presenting with vomiting, fever, coma and right hemiplegia at 26 months of age. Biochemical tests revealed hyperammonemia, hyperlactatemia, elevated glutamine level, elevated transaminase and disorder of prothrombin time. She was priory diagnosed with urea cycle disorders (UCDs). UCDs are caused by mutations in eight genes that regulate the synthesis of enzymes and cofactors involved in urea metabolism. Singleton whole exome sequencing was applied to screen causative variants in these genes in the patient at 6 years of age. The result showed one heterozygous stop loss mutation c.1065A>G in the OTC gene as a potential disease causing in the patient. The mutation c.1065A>G leads to alternation of stop codon to tryptophan, resulting in elongation of fourteen amino acids in ornithine transcarbamylase (OTC) protein (p.Ter355TrpextTer14). Sanger sequencing in the family revealed the mutation c.1065A>G was not present in healthy parents and brother. Therefore, this mutation is considered as a de novo mutation in the patient. The mutation c.1065A>G was conferred to pathogenic according to the standards and guidelines of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology with 1 strong (PS2), 3 moderate (PM2, PM4 and PM5) and 1 support criteria (PP2). Although OTC deficiency is an X-linked recessive inheritance, approximately 15% of females carrying heterozygous variants showed the late onset OTC deficiency. Therefore, in combination of clinical presentations, laboratory findings and molecular genetic analyses, we made a definitive diagnosis of the patient with late onset OTC deficiency, a disorder of UCDs.


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.


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