Publications by authors named "Pauline Marzin"

14 Publications

  • Page 1 of 1

Interplay between Histone and DNA Methylation Seen through Comparative Methylomes in Rare Mendelian Disorders.

Int J Mol Sci 2021 Apr 3;22(7). Epub 2021 Apr 3.

Université de Paris, Epigenetics and Cell Fate, CNRS UMR7216, 75013 Paris, France.

DNA methylation (DNAme) profiling is used to establish specific biomarkers to improve the diagnosis of patients with inherited neurodevelopmental disorders and to guide mutation screening. In the specific case of mendelian disorders of the epigenetic machinery, it also provides the basis to infer mechanistic aspects with regard to DNAme determinants and interplay between histone and DNAme that apply to humans. Here, we present comparative methylomes from patients with mutations in the de novo DNA methyltransferases DNMT3A and DNMT3B, in their catalytic domain or their N-terminal parts involved in reading histone methylation, or in histone H3 lysine (K) methylases NSD1 or SETD2 (H3 K36) or KMT2D/MLL2 (H3 K4). We provide disease-specific DNAme signatures and document the distinct consequences of mutations in enzymes with very similar or intertwined functions, including at repeated sequences and imprinted loci. We found that KMT2D and SETD2 germline mutations have little impact on DNAme profiles. In contrast, the overlapping DNAme alterations downstream of NSD1 or DNMT3 mutations underlines functional links, more specifically between NSD1 and DNMT3B at heterochromatin regions or DNMT3A at regulatory elements. Together, these data indicate certain discrepancy with the mechanisms described in animal models or the existence of redundant or complementary functions unforeseen in humans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22073735DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8038329PMC
April 2021

Sleep-disordered breathing and its management in children with rare skeletal dysplasias.

Am J Med Genet A 2021 Apr 28. Epub 2021 Apr 28.

AP-HP, Hôpital Necker-Enfants Malades, Pediatric Noninvasive Ventilation and Sleep Unit, Paris, France.

Sleep-disordered breathing (SDB) is common in patients with skeletal dysplasias. The aim of our study was to analyze SDB and respiratory management in children with rare skeletal dysplasias. We performed a retrospective analysis of patients with spondyloepiphyseal dysplasia congenita (SEDC), metatropic dysplasia (MD), spondyloepimetaphyseal dysplasia (SEMD), acrodysostosis (ADO), geleophysic dysplasia (GD), acromicric dysplasia (AD), and spondylocostal dysplasia (SCD) between April 2014 and October 2020. Polygraphic data, clinical management, and patients' outcome were analyzed. Thirty-one patients were included (8 SEDC, 3 MD, 4 SEMD, 1 ADO, 4 GD, 3 AD, and 8 SCD). Sixteen patients had obstructive sleep apnea (OSA): 11 patients (2 with SEDC, 1 with SEMD, 1 with ADO, 1 with GD, 2 with AD, and 4 with SCD) had mild OSA, 2 (1 SEMD and 1 GD) had moderate OSA, and 3 (1 SEDC, 1 MD, 1 SEMD) had severe OSA. Adenotonsillectomy was performed in one patient with SCD and mild OSA, and at a later age in two other patients with ADO and AD. The two patients with moderate OSA were treated with noninvasive ventilation (NIV) because of nocturnal hypoxemia. The three patients with severe OSA were treated with adenotonsillectomy (1 SEDC), adeno-turbinectomy and continuous positive airway pressure (CPAP; 1 MD), and with NIV (1 SEMD) because of nocturnal hypoventilation. OSA and/or alveolar hypoventilation is common in patients with skeletal dysplasias, underlining the importance of systematic screening for SDB. CPAP and NIV are effective treatments for OSA and nocturnal hypoventilation/hypoxemia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajmg.a.62236DOI Listing
April 2021

Geleophysic and acromicric dysplasias: natural history, genotype-phenotype correlations, and management guidelines from 38 cases.

Genet Med 2021 02 21;23(2):331-340. Epub 2020 Oct 21.

Fédération de Génétique médicale, Centre de référence pour les maladies osseuses constitutionnelles AP-HP, Hôpital Necker-Enfants malades, Paris, France.

Purpose: Geleophysic dysplasia (GD) and acromicric dysplasia (AD) are characterized by short stature, short extremities, and progressive joint limitation. In GD, cardiorespiratory involvement can result in poor prognosis. Dominant variants in the FBN1 and LTBP3 genes are responsible for AD or GD, whereas recessive variants in the ADAMTSL2 gene are responsible for GD only. The aim of this study was to define the natural history of these disorders and to establish genotype-phenotype correlations.

Methods: This monocentric retrospective study was conducted between January 2008 and December 2018 in a pediatric tertiary care center and included patients with AD or GD with identified variants (FBN1, LTBP3, or ADAMTSL2).

Results: Twenty-two patients with GD (12 ADAMTSL2, 8 FBN1, 2 LTBP3) and 16 patients with AD (15 FBN1, 1 LTBP3) were included. Early death occurred in eight GD and one AD. Among GD patients, 68% presented with heart valve disease and 25% developed upper airway obstruction. No AD patient developed life-threatening cardiorespiratory issues. A greater proportion of patients with either a FBN1 cysteine variant or ADAMTSL2 variants had a poor outcome.

Conclusion: GD and AD are progressive multisystemic disorders with life-threatening complications associated with specific genotype. A careful multidisciplinary follow-up is needed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41436-020-00994-xDOI Listing
February 2021

New perspectives on the treatment of skeletal dysplasia.

Ther Adv Endocrinol Metab 2020 3;11:2042018820904016. Epub 2020 Mar 3.

Clinical Genetics, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, IMAGINE Institute, Necker Enfants Malades Hospital, 149 rue de sevres, Paris, 75015, France.

The last few decades have been marked by the identification of numerous genes implicated in genetic disorders, helping in the elucidation of the underlying pathophysiology of these conditions. This has allowed new therapeutic approaches to emerge such as cellular therapy, gene therapy, or pharmacological therapy for various conditions. Skeletal dysplasias are good models to illustrate these scientific advances. Indeed, several therapeutic strategies are currently being investigated in osteogenesis imperfecta; there are ongoing clinical trials based on pharmacological approaches, targeting signaling pathways in achondroplasia and fibrodysplasia ossificans progressiva or the endoplasmic reticulum stress in metaphyseal dysplasia type Schmid or pseudoachondroplasia. Moreover, the treatment of hypophosphatasia or Morquio A disease illustrates the efficacy of enzyme drug replacement. To provide a highly specialized multidisciplinary approach, these treatments are managed by reference centers. The emergence of treatments in skeletal dysplasia provides new perspectives on the prognosis of these severe conditions and may change prenatal counseling in these diseases over the coming years.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/2042018820904016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7054735PMC
March 2020

SETD2 related overgrowth syndrome: Presentation of four new patients and review of the literature.

Am J Med Genet C Semin Med Genet 2019 12 23;181(4):509-518. Epub 2019 Oct 23.

Department of Medical Genetics, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, IMAGINE Institute, Necker Enfants Malades Hospital, Paris, France.

The common genes responsible for overgrowth syndromes play key roles in regulating transcription through histone modification and chromatin modeling. The SETD2 gene encoding a H3K36 trimethyltransferase is implicated in Sotos-like syndrome. This syndrome is characterized by postnatal overgrowth, macrocephaly, obesity, speech delay, and advanced carpal ossification. We report four new patients with constitutional SETD2 mutations and review nine earlier reported patients. Almost all patients presented with macrocephaly associated with advanced stature and obesity in half of the cases. In addition to these principal manifestations, neurodevelopmental disorders are common such as intellectual disability (83%), autism spectrum disorders (89%), and behavioral difficulties (100%) with aggressive outbursts (83%). A variety of features such as joint hypermobility (29%), hirsutism (33%), and naevi (50%) were also reported. Constitutional SETD2 mutations are intragenic loss-of-function variants with truncating (69%) and missense (31%) mutations. Functional studies are necessary to improve understanding of the pathogenicity of some missense SETD2 mutations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajmg.c.31746DOI Listing
December 2019

A 14q distal chromoanagenesis elucidated by whole genome sequencing.

Eur J Med Genet 2020 Apr 25;63(4):103776. Epub 2019 Sep 25.

Service de Génétique, Laboratoire de Cytogénétique Constitutionnelle, Hospices Civils de Lyon, Bron, France; GENDEV Team, Neurosciences Research Center of Lyon, INSERM U1028, CNRS UMR5292, UCBL1, 69677, Bron, France.

Chromoanagenesis represents an extreme form of genomic rearrangements involving multiple breaks occurring on a single or multiple chromosomes. It has been recently described in both acquired and rare constitutional genetic disorders. Constitutional chromoanagenesis events could lead to abnormal phenotypes including developmental delay and congenital anomalies, and have also been implicated in some specific syndromic disorders. We report the case of a girl presenting with growth retardation, hypotonia, microcephaly, dysmorphic features, coloboma, and hypoplastic corpus callosum. Karyotype showed a de novo structurally abnormal chromosome 14q31qter region. Molecular characterization using SNP-array revealed a complex unbalanced rearrangement in 14q31.1-q32.2, on the paternal chromosome 14, including thirteen interstitial deletions ranging from 33 kb to 1.56 Mb in size, with a total of 4.1 Mb in size, thus suggesting that a single event like chromoanagenesis occurred. To our knowledge, this is one of the first case of 14q distal deletion due to a germline chromoanagenesis. Genome sequencing allowed the characterization of 50 breakpoints, leading to interruption of 10 genes including YY1 which fit with the patient's phenotype. This precise genotyping of breaking junction allowed better definition of genotype-phenotype correlations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejmg.2019.103776DOI Listing
April 2020

Heterozygous FGFR1 mutation may be responsible for an incomplete form of osteoglophonic dysplasia, characterized only by radiolucent bone lesions and teeth retentions.

Eur J Med Genet 2020 Feb 15;63(2):103729. Epub 2019 Jul 15.

Department of Medical Genetics, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, IMAGINE Institute, Necker Enfants Malades Hospital, Paris, France. Electronic address:

Non-ossifying fibromas are seen in different disorders recognizable by specific features. Indeed, osteoglophonic dysplasia (OD) is characterized by radiolucent bone lesions associated with severe short stature, dysmorphism and failure of dental eruption. This syndrome is caused by heterozygous activating mutations in the immunoglobulin-like D3 domain of the FGFR1 gene, encoding a tyrosine kinase. Here, we report three patients from the same family presenting with radiolucent bone lesions and teeth retentions. Exome sequencing allowed identification of a novel mutation c.917C > T, p. Pro306Leu in exon 7 of the FGFR1 gene. Our patients present with normal stature and no severe dysmorphism. This report describes a mild form of OD and expands the phenotype related to FGFR1 mutations. These findings emphasize the need to consider FGFR1 variants in the case of multiple non-ossifying bone lesions associated with dental eruption anomalies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejmg.2019.103729DOI Listing
February 2020

Correction: IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients.

Genet Med 2019 Aug;21(8):1897-1898

APHP, Service de genetique medicale, Necker- Enfants Malades Hospital, Imagine Institute, Paris Descartes University, Paris, France.

This Article was originally published under Nature Research's License to Publish, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the Article have been modified accordingly.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41436-018-0327-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7608434PMC
August 2019

IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients.

Genet Med 2019 04 12;21(4):837-849. Epub 2018 Sep 12.

APHP, Service de genetique medicale, Necker-Enfants Malades Hospital, Imagine Institute, Paris Descartes University, Paris, France.

Purpose: Variants in IQSEC2, escaping X inactivation, cause X-linked intellectual disability with frequent epilepsy in males and females. We aimed to investigate sex-specific differences.

Methods: We collected the data of 37 unpublished patients (18 males and 19 females) with IQSEC2 pathogenic variants and 5 individuals with variants of unknown significance and reviewed published variants. We compared variant types and phenotypes in males and females and performed an analysis of IQSEC2 isoforms.

Results: IQSEC2 pathogenic variants mainly led to premature truncation and were scattered throughout the longest brain-specific isoform, encoding the synaptic IQSEC2/BRAG1 protein. Variants occurred de novo in females but were either de novo (2/3) or inherited (1/3) in males, with missense variants being predominantly inherited. Developmental delay and intellectual disability were overall more severe in males than in females. Likewise, seizures were more frequently observed and intractable, and started earlier in males than in females. No correlation was observed between the age at seizure onset and severity of intellectual disability or resistance to antiepileptic treatments.

Conclusion: This study provides a comprehensive overview of IQSEC2-related encephalopathy in males and females, and suggests that an accurate dosage of IQSEC2 at the synapse is crucial during normal brain development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41436-018-0268-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6752297PMC
April 2019

Early-onset encephalopathy with paroxysmal movement disorders and epileptic seizures without hemiplegic attacks: About three children with novel ATP1A3 mutations.

Brain Dev 2018 Oct 31;40(9):768-774. Epub 2018 May 31.

Centre de Référence Déficience Intellectuelle de Causes Rares, Paris, France; APHP, Service de Neurologie Pédiatrique, Hôpital Armand Trousseau, Paris, France; APHP, Centre de Référence des Mouvements Anormaux de l'Enfant, Hôpital Armand Trousseau, Paris, France; Sorbonne Université, GRC n°19, Pathologies Congénitales du Cervelet-LeucoDystrophies, AP-HP, Hôpital Armand Trousseau, F-75012 Paris, France. Electronic address:

Objective: Heterozygous mutations in the ATP1A3 gene are responsible for various neurological disorders, ranging from early-onset alternating hemiplegia of childhood to adult-onset dystonia-parkinsonism. Next generation sequencing allowed the description of other phenotypes, including early-onset epileptic encephalopathy in two patients. We report on three more patients carrying ATP1A3 mutations with a close phenotype and discuss the relationship of this phenotype to alternating hemiplegia of childhood.

Methods: The patients' DNA underwent next generation sequencing. A retrospective analysis of clinical case records is reported.

Results: Each of the three patients had an unreported heterozygous de novo sequence variant in ATP1A3. These patients shared a similar phenotype characterized by early-onset attacks of movement disorders, some of which proved to be epileptic, and severe developmental delay. (Hemi)plegic attacks had not been considered before genetic testing.

Significance: Together with the two previously reported cases, our patients confirm that ATP1A3 mutations are associated with a phenotype combining features of early-onset encephalopathy, epilepsy and dystonic fits, as in the most severe forms of alternating hemiplegia of childhood, but in which (hemi)plegic attacks are absent or only suspected retrospectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.braindev.2018.05.008DOI Listing
October 2018

Potential selection of genetically balanced spermatozoa based on the hypo-osmotic swelling test in chromosomal rearrangement carriers.

Reprod Biomed Online 2017 Oct 27;35(4):372-378. Epub 2017 Jun 27.

Medical Genetics Department, APHP, INSERM UMR_S933, Armand-Trousseau Hospital, 75012 Paris, France.

Chromosomal translocations and other balanced rearrangements, although usually associated with a normal phenotype, can lead to the transmission of an abnormal unbalanced genome to the offspring. Balanced and unbalanced spermatozoa, being indistinguishable, cannot be selected or deselected for prior to IVF and pre-implantation genetic diagnosis. Spermatozoa from 16 chromosomal rearrangement carriers were studied. After incubation in a hypo-osmotic solution (hypo-osmotic swelling test, or HOST), spermatozoa were fixed on microscope slides. The chromosomally balanced or unbalanced status corresponding to each observed class of flagellar conformation was evaluated through fluorescent in-situ hybridization (FISH). We show here a specific type of spermatozoa, with a distinct flagellar conformation that was associated with a balanced genetic content. HOST is a simple, low-cost and time-honoured procedure initially developed to distinguish immotile viable from non-viable spermatozoa. We demonstrate that it can also be used to identify genetically balanced spermatozoa in chromosomal rearrangement carriers, with a 96% decrease in the proportion of unbalanced spermatozoa after selection. This may potentially improve reproductive prognosis in affected couples if used prior to pre-implantation genetic diagnosis (PGD), and clinical utility and efficacy should be evaluated in further studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rbmo.2017.06.017DOI Listing
October 2017

Genetic and phenotypic dissection of 1q43q44 microdeletion syndrome and neurodevelopmental phenotypes associated with mutations in ZBTB18 and HNRNPU.

Hum Genet 2017 04 10;136(4):463-479. Epub 2017 Mar 10.

Institut de Génétique Médicale, CHRU de Lille, Lille, France.

Subtelomeric 1q43q44 microdeletions cause a syndrome associating intellectual disability, microcephaly, seizures and anomalies of the corpus callosum. Despite several previous studies assessing genotype-phenotype correlations, the contribution of genes located in this region to the specific features of this syndrome remains uncertain. Among those, three genes, AKT3, HNRNPU and ZBTB18 are highly expressed in the brain and point mutations in these genes have been recently identified in children with neurodevelopmental phenotypes. In this study, we report the clinical and molecular data from 17 patients with 1q43q44 microdeletions, four with ZBTB18 mutations and seven with HNRNPU mutations, and review additional data from 37 previously published patients with 1q43q44 microdeletions. We compare clinical data of patients with 1q43q44 microdeletions with those of patients with point mutations in HNRNPU and ZBTB18 to assess the contribution of each gene as well as the possibility of epistasis between genes. Our study demonstrates that AKT3 haploinsufficiency is the main driver for microcephaly, whereas HNRNPU alteration mostly drives epilepsy and determines the degree of intellectual disability. ZBTB18 deletions or mutations are associated with variable corpus callosum anomalies with an incomplete penetrance. ZBTB18 may also contribute to microcephaly and HNRNPU to thin corpus callosum, but with a lower penetrance. Co-deletion of contiguous genes has additive effects. Our results confirm and refine the complex genotype-phenotype correlations existing in the 1qter microdeletion syndrome and define more precisely the neurodevelopmental phenotypes associated with genetic alterations of AKT3, ZBTB18 and HNRNPU in humans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00439-017-1772-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5360844PMC
April 2017