0000000000311996

AUTHOR

Martin Zenker

Mutation Analysis of Core Binding Factor A1 in Patients with Cleidocranial Dysplasia

SummaryCleidocranial dysplasia (CCD) is a dominantly inherited disorder characterized by patent fontanelles, wide cranial sutures, hypoplasia of clavicles, short stature, supernumerary teeth, and other skeletal anomalies. We recently demonstrated that mutations in the transcription factor CBFA1, on chromosome 6p21, are associated with CCD. We have now analyzed the CBFA1 gene in 42 unrelated patients with CCD. In 18 patients, mutations were detected in the coding region of the CBFA1 gene, including 8 frameshift, 2 nonsense, and 9 missense mutations, as well as 2 novel polymorphisms. A cluster of missense mutations at arginine 225 (R225) identifies this residue as crucial for CBFA1 function. …

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Hydrops, fetal pleural effusions and chylothorax in three patients with CBL mutations.

Fetal hydrops, fetal pleural effusions, hydrothorax, and chylothorax, may be associated with various genetic disorders, in particular with the Noonan, cardio-facio-cutaneous and Costello syndromes. These syndromes, collectively called RASopathies, are caused by mutations in the RAS/MAPK pathway, which is known to play a major role in lymphangiogenesis. Recently, germline mutations in the Casitas B-cell lymphoma (CBL) gene were reported in 25 patients and of these, 20 had juvenile myelomonocytic leukemia (JMML). The disorder was named "CBL syndrome" or "Noonan syndrome-like disorder with or without juvenile myelomonocytic leukemia" (NSLL). To date, prenatal abnormalities have not been report…

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Correction: The landscape of epilepsy-related GATOR1 variants

International audience; The original version of this article contained an error in the spelling of the author Erik H. Niks, which was incorrectly given as Erik Niks. This has now been corrected in both the PDF and HTML versions of the article.

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NFIB Haploinsufficiency Is Associated with Intellectual Disability and Macrocephaly

The nuclear factor I (NFI) family of transcription factors play an important role in normal development of multiple organs. Three NFI family members are highly expressed in the brain, and deletions or sequence variants in two of these, NFIA and NFIX, have been associated with intellectual disability (ID) and brain malformations. NFIB, however, has not previously been implicated in human disease. Here, we present a cohort of 18 individuals with mild ID and behavioral issues who are haploinsufficient for NFIB. Ten individuals harbored overlapping microdeletions of the chromosomal 9p23-p22.2 region, ranging in size from 225 kb to 4.3 Mb. Five additional subjects had point sequence variations c…

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The landscape of epilepsy-related GATOR1 variants

Purpose:\ud \ud To define the phenotypic and mutational spectrum of epilepsies related to DEPDC5, NPRL2 and NPRL3 genes encoding the GATOR1 complex, a negative regulator of the mTORC1 pathway.\ud \ud Methods:\ud \ud We analyzed clinical and genetic data of 73 novel probands (familial and sporadic) with epilepsy-related variants in GATOR1-encoding genes and proposed new guidelines for clinical interpretation of GATOR1 variants.\ud \ud Results:\ud \ud The GATOR1 seizure phenotype consisted mostly in focal seizures (e.g., hypermotor or frontal lobe seizures in 50%), with a mean age at onset of 4.4 years, often sleep-related and drug-resistant (54%), and associated with focal cortical dysplasia…

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Childhood cancer predisposition syndromes-A concise review and recommendations by the Cancer Predisposition Working Group of the Society for Pediatric Oncology and Hematology.

Heritable predisposition is an important cause of cancer in children and adolescents. Although a large number of cancer predisposition genes and their associated syndromes and malignancies have already been described, it appears likely that there are more pediatric cancer patients in whom heritable cancer predisposition syndromes have yet to be recognized. In a consensus meeting in the beginning of 2016, we convened experts in Human Genetics and Pediatric Hematology/Oncology to review the available data, to categorize the large amount of information, and to develop recommendations regarding when a cancer predisposition syndrome should be suspected in a young oncology patient. This review su…

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Recurrent Mutations in the Basic Domain of TWIST2 Cause Ablepharon Macrostomia and Barber-Say Syndromes

Contains fulltext : 153827.pdf (Publisher’s version ) (Open Access) Ablepharon macrostomia syndrome (AMS) and Barber-Say syndrome (BSS) are rare congenital ectodermal dysplasias characterized by similar clinical features. To establish the genetic basis of AMS and BSS, we performed extensive clinical phenotyping, whole exome and candidate gene sequencing, and functional validations. We identified a recurrent de novo mutation in TWIST2 in seven independent AMS-affected families, as well as another recurrent de novo mutation affecting the same amino acid in ten independent BSS-affected families. Moreover, a genotype-phenotype correlation was observed, because the two syndromes differed based s…

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Specific mosaicKRASmutations affecting codon 146 cause oculoectodermal syndrome and encephalocraniocutaneous lipomatosis

Oculoectodermal syndrome (OES) and encephalocraniocutaneous lipomatosis (ECCL) are rare disorders that share many common features, such as epibulbar dermoids, aplasia cutis congenita, pigmentary changes following Blaschko lines, bony tumor-like lesions, and others. About 20 cases with OES and more than 50 patients with ECCL have been reported. Both diseases were proposed to represent mosaic disorders, but only very recently whole-genome sequencing has led to the identification of somatic KRAS mutations, p.Leu19Phe and p.Gly13Asp, in affected tissue from two individuals with OES. Here we report the results of molecular genetic studies in three patients with OES and one with ECCL. In all four…

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Haploinsufficiency of the NOTCH1 receptor as a cause of Adams-Oliver syndrome with variable cardiac anomalies

Background— Adams–Oliver syndrome (AOS) is a rare disorder characterized by congenital limb defects and scalp cutis aplasia. In a proportion of cases, notable cardiac involvement is also apparent. Despite recent advances in the understanding of the genetic basis of AOS, for the majority of affected subjects, the underlying molecular defect remains unresolved. This study aimed to identify novel genetic determinants of AOS. Methods and Results— Whole-exome sequencing was performed for 12 probands, each with a clinical diagnosis of AOS. Analyses led to the identification of novel heterozygous truncating NOTCH1 mutations (c.1649dupA and c.6049_6050delTC) in 2 kindreds in which AOS was segregat…

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Case report supporting that the Barber-Say and ablepharon macrostomia syndromes could represent one disorder.

We report on a 7-year-old girl with unequivocal features of Barber-Say syndrome (BSS): generalized hypertrichosis especially at the back, dry lax skin, macrostomia, thin lips, cup-shaped ears, bulbous nose, hypoplastic nipples, and abnormal external genitalia. She also demonstrated conductive hearing impairment and microblepharon. BSS has been reported with ectropion (not present in our patient), but ablepharon and microblepharon (i.e., absent or hypoplastic eyelids) have always been considered as hallmarks of ablepharon macrostomia syndrome (AMS). This is the first report of microblepharon in BSS. Other authors have discussed that BSS and AMS could possibly represent one syndrome, and our …

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Mutations in PRDM15 Are a Novel Cause of Galloway-Mowat Syndrome

Background Galloway-Mowat syndrome (GAMOS) is characterized by neurodevelopmental defects and a progressive nephropathy, which typically manifests as steroid-resistant nephrotic syndrome. The prognosis of GAMOS is poor, and the majority of children progress to renal failure. The discovery of monogenic causes of GAMOS has uncovered molecular pathways involved in the pathogenesis of disease. Methods Homozygosity mapping, whole-exome sequencing, and linkage analysis were used to identify mutations in four families with a GAMOS-like phenotype, and high-throughput PCR technology was applied to 91 individuals with GAMOS and 816 individuals with isolated nephrotic syndrome. In vitro and in vivo st…

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Galloway-Mowat syndrome: New insights from bioinformatics and expression during Xenopus embryogenesis.

Abstract Galloway-Mowat syndrome (GAMOS) is a rare developmental disease. Patients suffer from congenital brain anomalies combined with renal abnormalities often resulting in an early-onset steroid-resistant nephrotic syndrome. The etiology of GAMOS has a heterogeneous genetic contribution. Mutations in more than 10 different genes have been reported in GAMOS patients. Among these are mutations in four genes encoding members of the human KEOPS ( k inase, e ndopeptidase and o ther p roteins of small s ize) complex, including OSGEP, TP53RK, TPRKB and LAGE3. Until now, these components have been functionally mainly investigated in bacteria, eukarya and archaea and in humans in the context of t…

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Barber-Say Syndrome and Ablepharon-Macrostomia Syndrome: A Patient's View

Barber-Say syndrome (BSS) and ablepharon-macrostomia syndrome (AMS) are infrequently reported congenital malformation disorders caused by mutations in the <i>TWIST2</i> gene. Both are characterized by abnormalities in ectoderm-derived structures and cause a very unusual morphology of mainly the face in individuals with otherwise normal cognition and normal physical functioning. We studied the impact that the presence of BSS and AMS has on psychosocial functioning of affected individuals and their families, using their point of view to start with. We tabulated frequently asked questions from affected individuals and families, and a parent of an affected child and an affected adul…

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Congenital nephrosis, mesangial sclerosis, and distinct eye abnormalities with microcoria: An autosomal recessive syndrome

We observed the occurrence of congenital nephrotic syndrome (CNS) and distinct ocular anomalies in two unrelated families. Eleven children from both families presented with a similar course of renal disease starting with nephrotic syndrome and renal failure prenatally or immediately after birth that resulted in death before the age of 2 months. Kidney histopathology showed diffuse mesangial sclerosis (DMS). Clinically obvious eye abnormalities were recognized in six of the eight patients in whom sufficient clinical data were available. Ocular anomalies included enlarged or large appearing corneae in some cases suggesting buphthalmos, and extremely narrow, nonreactive pupils (microcoria). Pa…

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