Autosomal dominant Alport syndrome due to a COL4A4 mutation with an additional ESPN variant detected by whole-exome analysis

Morning glory syndrome (MGS) is a rare congenital optic disc anomaly with a characteristic fundal finding with severe visual impairment. It may occur in association with various systemic manifestations, even though most of the reported cases were isolated. A 6-year-old male visited the nephrology clinic with a history of microscopic hematuria and at the age of 12 years, he was diagnosed thin glomerular basement membrane nephropathy by kidney biopsy. After the following years, the patient had progressive deterioration of visual acuity, and diagnosed as MGS. Whole Exome Sequencing of this patient and his mother revealed heterozygous COL4A4 mutations [c.81_86del (p.Ile29_Leu30del)]. It is more reasonable to consider MGS seen in this patient as a coincidental finding of autosomal dominant Alport syndrome. To our knowledge, this case represents the first case report of autosomal dominant Alport syndrome associated with MGS.

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A Novel Mutation in COL4A1 Gene in a Chinese Family with Pontine Autosomal Dominant Microangiopathy and Leukoencephalopathy

Translational Stroke Research ◽

10.1007/s12975-021-00926-0 ◽

2021 ◽

Author(s):

Qing Li ◽

Chengfeng Wang ◽

Wei Li ◽

Zaiqiang Zhang ◽

Shanshan Wang ◽

...

Keyword(s):

Basement Membrane ◽

Skin Biopsy ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Autosomal Dominant ◽

Chinese Family ◽

Heterozygous Mutation ◽

Collagen Type Iv ◽

Lacunar Infarcts ◽

Whole Exome

AbstractPontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL) is a rare hereditary cerebral small vessel disease. We report a novel collagen type IV alpha 1 (COL4A1) gene mutation in a Chinese family with PADMAL. The index case was followed up for 6 years. Neuroimaging, whole-exome sequencing, skin biopsy, and pedigree analysis were performed. She initially presented with minor head injury at age 38. MRI brain showed chronic lacunar infarcts in the pons, left thalamus, and right centrum semiovale. Extensive workup was unremarkable except for a patent foramen ovale (PFO). Despite anticoagulation, PFO closure, and antiplatelet therapy, the patient had recurrent lacunar infarcts in the pons and deep white matter, as well as subcortical microhemorrhages. Whole-exome sequencing demonstrated a novel c.*34G > T mutation in the 3′ untranslated region of COL4A1 gene. Skin biopsy subsequently demonstrated thickening of vascular basement membrane, proliferation of endothelial cells, and stenosis of vascular lumen. Three additional family members had gene testing and 2 of them were found to have the same heterozygous mutation. Of the 18 individuals in the pedigree of 3 generations, 12 had clinical and MRI evidence of PADMAL. The mechanisms of both ischemic and hemorrhagic stroke are likely the overexpression of COLT4A1 in the basement membrane and frugality of the vessel walls. Our findings suggest that the novel c.*34G > T mutation appears to have the same functional consequences as the previously reported COL4A1 gene mutations in patients with PADMAL and multi-infarct dementia of Swedish type.

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A Case Report of a Prenatally Missed Mowat-Wilson Syndrome With Isolated Corpus Callosum Agenesis

Child Neurology Open ◽

10.1177/2329048x211006511 ◽

2021 ◽

Vol 8 ◽

pp. 2329048X2110065

Author(s):

Nesrin Şenbil ◽

Zeynep Arslan ◽

Derya Beyza Sayın Kocakap ◽

Yasemin Bilgili

Keyword(s):

Corpus Callosum ◽

Autosomal Dominant ◽

Genetic Disorder ◽

Gene Mutations ◽

Hirschsprung Disease ◽

Agenesis Of Corpus Callosum ◽

Whole Exome ◽

Congenital Cardiac Anomalies ◽

History Of ◽

Gene Mutation Analysis

Mowat–Wilson syndrome (MWS) is an autosomal dominant genetic disorder caused by ZEB2 gene mutations, manifesting with unique facial characteristics, moderate to severe intellectual problems, and congenital malformations as Hirschsprung disease, genital and ophthalmological anomalies, and congenital cardiac anomalies. Herein, a case of 1-year-old boy with isolated agenesis of corpus callosum (IACC) in the prenatal period is presented. He was admitted postnatally with Hirschsprung disease (HSCR), hypertelorism, uplifted earlobes, deeply set eyes, frontal bossing, oval-shaped nasal tip, ‘‘M’’ shaped upper lip, opened mouth and prominent chin, and developmental delay. Hence, MWS was primarily considered and confirmed by the ZEB2 gene mutation analysis. His karyotype was normal. He had a history of having a prenatally terminated brother with similar features. Antenatally detected IACC should prompt a detailed investigation including karyotype and microarray; even if they are normal then whole exome sequencing (WES) should be done.

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MO046NGS PANEL PERFORMANCE IN THE DIAGNOSIS OF HEREDITARY RENAL DISEASE IN SOUTHERN SPAIN

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfab080.0018 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

María del Mar Del Águila García ◽

Antonio M Poyatos Andújar ◽

Ana Isabel Morales García ◽

Margarita Martínez Atienza ◽

Susana García Linares ◽

...

Keyword(s):

Kidney Disease ◽

Renal Disease ◽

Polycystic Kidney Disease ◽

Genetic Study ◽

Alport Syndrome ◽

Autosomal Dominant ◽

Kidney Diseases ◽

Polycystic Kidney ◽

Autosomal Dominant Polycystic Kidney ◽

Hereditary Renal Disease

Abstract Background and Aims Hereditary renal disease (HRD) is still underdiagnosed: although we know aspects related to autosomal dominant polycystic kidney disease (ADPKD), we know little about the incidence and prevalence of other entities such as Alport syndrome. Altogether, HRD can represent 15% of individuals undergoing renal replacement therapy (RRT) or could even be higher. The advancement of genetics at the healthcare level let to achieve accurate and early renal diagnoses, as well as the incorporation of genetic counseling to families, all of which will result in better management of the disease in its initial stages and the possibility of offering reproductive options that avoid transmission to offspring. Our objective is to know the performance offered by the implementation of the ERH panel through Next Generation Sequencing (NGS) in our healthcare area. Method Observational-descriptive study of 259 probands (141 men / 118 women), mean age of 46 years (30 pediatric / 123 over 50 years), with chronic kidney disease and suspected hereditary cause attended in the specialized consultation of our centers from October 2018 to October 2020. The DNA extracted from leukocytes obtained by venipuncture was processed with Nephropathies Solution version 3 panel (SOPHiA Genetics) according to the manufacturer's protocol. This panel covers the coding regions and splicing junctions of 44 HRD-related genes such as nephrotic syndromes, polycystic kidney diseases, Bartter syndromes, Alport syndrome, CAKUT or tubulopathies (table 1). The sequencing of the libraries was done in a MiSeq (Illumina Inc), the bioinformatic analysis of the data and annotation of variants was performed using the SOPHiA DDM 5.8.0.3 software, and the revision of variants by consulting the main databases (ClinVar, Exac, HGMD, NCBI, PKD Foundation, LOVD). Results The panel was informative (pathogenic or probably pathogenic) in 80/259 patients (31%) and 56/259 cases (21.66%) of variants of uncertain significance (VSI) were detected. Autosomal dominant polycystic kidney disease accounted for 76.2% of the variants identified (56.2% PKD1, 20% PKD2), following Alport syndrome with 15% and the alterations in the PKHD1 gene associated with renal polycystic disease in its recessive form with about 4% (Figure 1). We have also identified a case of autosomal dominant tubulointerstitial kidney disease associated with the UMOD gene that was not suspected until the genetic study was performed. We highlight that 45% (36/80) of the variants identified as responsible for the renal disease are not yet described. Overall, the most prevalent type of mutation is that which produces displacement in the reading frame or frameshift (Figure 2). Individually, frameshift is the most frequent alteration in PKD1, PKD2 and COL4A5, while for PKHD1, COL4A3 and COL4A4 it is missense. Conclusion Our NGS HRD panel a) offers an adequate diagnostic performance at the healthcare level, with definitive results in 1 out of 3 cases and has also allowed the performance of many carrier studies among family members b) is able of diagnosing the most frequent disease, ADPKD and Alport syndrome, as well as unresolved or poorly characterized cases, and c) opens the horizon for new diagnoses, all without increasing costs by outsourcing services. All this makes the genetic study of renal pathology a useful and efficient strategy. These results encourage us to enhance the resources in this area that we consider to be of strategic value.

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OA 10.05 Non-Invasive Molecular Profiling in NSCLC by Targeted and Whole Exome Analysis of Plasma cfDNA

Journal of Thoracic Oncology ◽

10.1016/j.jtho.2017.09.385 ◽

2017 ◽

Vol 12 (11) ◽

pp. S1772

Author(s):

M. Cheng ◽

J. Yang ◽

M. Shady ◽

P. Ulz ◽

E. Heitzer ◽

...

Keyword(s):

Molecular Profiling ◽

Non Invasive ◽

Whole Exome ◽

Exome Analysis

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A Novel COMP Mutated Allele Identified in a Chinese Family with Pseudoachondroplasia

BioMed Research International ◽

10.1155/2021/6678531 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Bing-Bing Guo ◽

Jie-Yuan Jin ◽

Zhuang-Zhuang Yuan ◽

Lei Zeng ◽

Rong Xiang

Keyword(s):

Extracellular Matrix ◽

Cartilage Oligomeric Matrix Protein ◽

Matrix Protein ◽

Autosomal Dominant ◽

Novel Mutation ◽

Chinese Family ◽

The Novel ◽

Structure Model ◽

Whole Exome ◽

Nucleotide Mutation

Pseudoachondroplasia (PSACH) is an autosomal dominant skeletal dysplasia with an estimated incidence of ~1/60000 that is characterized by disproportionate short stature, brachydactyly, joint laxity, and early-onset osteoarthritis. COMP encodes the cartilage oligomeric matrix protein, which is expressed predominantly in the extracellular matrix (ECM) surrounding the cells that make up cartilage, ligaments, and tendons. Mutations in COMP are known to give rise to PSACH. In this study, we identified a novel nucleotide mutation (NM_000095.2: c.1317C>G, p.D439E) in COMP responsible for PSACH in a Chinese family by employing whole-exome sequencing (WES) and built the structure model of the mutant protein to clarify its pathogenicity. The novel mutation cosegregated with the affected individuals. Our study expands the spectrum of COMP mutations and further provides additional genetic testing information for other PSACH patients.

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Prenatal Diagnosis of Holt–Oram Syndrome With a Novel Mutation of TBX5 Gene: A Case Report

Frontiers in Pediatrics ◽

10.3389/fped.2021.737633 ◽

2021 ◽

Vol 9 ◽

Author(s):

Guan-nan He ◽

Xue-yan Wang ◽

Min Kang ◽

Xi-min Chen ◽

Na Xi ◽

...

Keyword(s):

Septal Defect ◽

Autosomal Dominant ◽

Novel Mutation ◽

Splice Donor ◽

Autosomal Dominant Disorder ◽

Cubitus Valgus ◽

Case Presentation ◽

Whole Exome ◽

The Right ◽

Tbx5 Gene

Background: Holt–Oram syndrome (HOS) is an autosomal dominant disorder caused by mutations of TBX5 gene.Case presentation: We report a fetus with HOS diagnosed sonographically at 23 weeks of gestation. The fetal parents are non-consanguineous. The fetus exhibited short radius and ulna, inability to supinate the hands, absence of the right thumb, and heart ventricular septal defect (VSD), while the fetal father exhibited VSD and short radius and ulna only. Fetal brother had cubitus valgus and thumb adduction, except for VSD, short radius and ulna. The pregnancy was terminated. Whole-exome sequencing (WES) revealed a novel mutation in the TBX5 (c.510+1G>A) in the fetus inherited from the father. The variant (c.510+1G>A) occurs at splice donor and may alter TBX5 gene function by impact on splicing. It was not previously reported in China.Conclusion: Our case reported a novel mutation in TBX5, which expanded the known genetic variants associated with HOS.

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Identification of a novel pathogenic missense mutation in PRPF31 using whole exome sequencing: a case report

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2017-311405 ◽

2018 ◽

Vol 103 (6) ◽

pp. 761-767 ◽

Cited By ~ 2

Author(s):

Laura Bryant ◽

Olga Lozynska ◽

Anson Marsh ◽

Tyler E Papp ◽

Lucas van Gorder ◽

...

Keyword(s):

Exome Sequencing ◽

Missense Mutation ◽

Whole Exome Sequencing ◽

Protein Trafficking ◽

Protein Misfolding ◽

Autosomal Dominant ◽

Null Alleles ◽

Incomplete Penetrance ◽

Missense Mutations ◽

Whole Exome

BackgroundVariants in PRPF31, which encodes pre-mRNA processing factor 31 homolog, are known to cause autosomal-dominant retinitis pigmentosa (adRP) with incomplete penetrance. However, the majority of mutations cause null alleles, with only two proven pathogenic missense mutations. We identified a novel missense mutation in PRPF31 in a family with adRP.MethodsWe performed whole exome sequencing to identify possible pathogenic mutations in the proband of a family with adRP. Available affected family members had a full ophthalmological evaluation including kinetic and two-colour dark adapted static perimetry, electroretinography and multimodal imaging of the retina. Two patients had evaluations covering nearly 20 years. We carried out segregation analysis of the probable mutation, PRPF31 c.590T>C. We evaluated the cellular localisation of the PRPF31 variant (p.Leu197Pro) compared with the wildtype PRPF31 protein.ResultsPRPF31 c.590T>C segregated with the disease in this four-generation autosomal dominant pedigree. There was intrafamilial variability in disease severity. Nyctalopia and mid-peripheral scotomas presented from the second to the fourth decade of life. There was severe rod >cone dysfunction. Visual acuity (VA) was relatively intact and was maintained until later in life, although with marked interocular asymmetries. Laboratory studies showed that the mutant PRPF31 protein (p.Leu197Pro) does not localise to the nucleus, unlike the wildtype PRPF31 protein. Instead, mutant protein resulted in punctate localisation to the cytoplasm.Conclusionsc.590T>C is a novel pathogenic variant in PRPF31 causing adRP with incomplete penetrance. Disease may be due to protein misfolding and associated abnormal protein trafficking to the nucleus.

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Dominant SCN2A Mutation Causes Familial Episodic Ataxia and Impairment of Speech Development

Neuropediatrics ◽

10.1055/s-0038-1668141 ◽

2018 ◽

Vol 49 (06) ◽

pp. 379-384 ◽

Cited By ~ 7

Author(s):

Kerstin Becker ◽

Peter Herkenrath ◽

Christoph Düchting ◽

Friederike Körber ◽

Pablo Landgraf ◽

...

Keyword(s):

Autosomal Dominant ◽

Index Patient ◽

Speech Development ◽

Episodic Ataxia ◽

Cerebellar Hemisphere ◽

First Episode ◽

Whole Exome ◽

Neurologic Disorders ◽

Left Cerebellar Hemisphere ◽

Impaired Speech

AbstractMutations in SCN2A are associated with a heterogeneous clinical spectrum including epilepsy and autism. Here, we have identified a peculiar phenotype associated with vaccination related exacerbations of ataxia. We report the first family with three individuals affected by SCN2A-associated episodic ataxia (EA) with impaired speech development. The index patient manifested his first episode of subacute cerebellar ataxia at the age of 12 months, 3 weeks after vaccinations for measles, mumps, rubella, and varicella. Cranial magnetic resonance imaging showed a lesion of the left cerebellar hemisphere, which was first considered as a potential cause of the ataxia. The patient fully recovered within 3 weeks, but developed three very similar episodes of transient ataxia within the following 24 months. Whole exome sequencing of the index patient revealed a heterozygous autosomal-dominant mutation in SCN2A (NM_021007, c.4949T > C; p.L1650P), which was confirmed in the likewise affected mother, and was then also identified in the younger brother who developed the first episode of ataxia. We hereby extend the recently described spectrum of SCN2A-associated neurologic disorders, emphasizing that SCN2A mutations should also be considered in familial cases of EA. Coincidental imaging findings or other associated events such as immunizations should not protract genetic investigations.

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Prevalence of clinical, pathological and molecular features of glomerular basement membrane nephropathy caused by COL4A3 or COL4A4 mutations: a systematic review

Clinical Kidney Journal ◽

10.1093/ckj/sfz176 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1025-1036 ◽

Cited By ~ 3

Author(s):

Andreas Matthaiou ◽

Tsielestina Poulli ◽

Constantinos Deltas

Keyword(s):

Basement Membrane ◽

Alport Syndrome ◽

Autosomal Dominant ◽

Wide Spectrum ◽

Age At Onset ◽

Histological Finding ◽

Basement Membranes ◽

Thin Basement Membrane Nephropathy ◽

Molecular Features ◽

Thin Basement Membrane Disease

Abstract Background Patients heterozygous for COL4A3 or COL4A4 mutations show a wide spectrum of disease, extending from familial isolated microscopic haematuria, as a result of thin basement membranes (TBMs), to autosomal dominant Alport syndrome (ADAS) and end-stage renal disease (ESRD). Many patients are mentioned in the literature under the descriptive diagnosis of TBM nephropathy (TBMN), in which case it actually describes a histological finding that represents the carriers of autosomal recessive Alport syndrome (ARAS), a severe glomerulopathy, as most patients reach ESRD at a mean age of 25 years. Methods We performed a systematic literature review for patients with heterozygous COL4A3/A4 mutations with the aim of recording the spectrum and frequency of pathological features. We searched three databases (PubMed, Embase and Scopus) using the keywords ‘Autosomal Dominant Alport Syndrome’ OR ‘Thin Basement Membrane Disease’ OR ‘Thin Basement Membrane Nephropathy’. We identified 48 publications reporting on 777 patients from 258 families. Results In total, 29% of the patients developed chronic kidney disease (CKD) and 15.1% reached ESRD at a mean age of 52.8 years. Extrarenal features and typical Alport syndrome (AS) findings had a low prevalence in patients as follows: hearing loss, 16%; ocular lesions, 3%; basement membrane thickening, 18.4%; and podocyte foot process effacement, 6.9%. Data for 76 patients from 54 families emphasize extensive inter- and intrafamilial heterogeneity, with age at onset of ESRD ranging between 21 and 84 years (mean 52.8). Conclusions The analysis enabled a comparison of the clinical course of patients with typical ARAS or X-linked AS with those with heterozygous COL4A mutations diagnosed with TBMN or ADAS. Despite the consequence of a potential ascertainment bias, an important outcome is that TBM poses a global high risk of developing severe CKD, over a long follow-up, with a variable spectrum of other findings. The results are useful to practicing nephrologists for better evaluation of patients.

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