Dyskeratosis congenita (DC) is a rare, inherited, bone marrow failure syndrome caused by premature telomere shortening. The classic mucocutaneous triad of clinical features comprises reticulated skin pigmentation, nail dysplasia, and oral leukoplakia. Multiple somatic features, including bone marrow failure, pulmonary fibrosis, and liver disease, are also common. Read More
CRIIS (Interdisciplinary, Interdepartmental and Specialistic Reference Center for Early Diagnosis of Scleroderma, Treatment of Sclerodermic Ulcers and Videocapillaroscopy), Sandro Pertini Hospital, Rome, Italy.
Background: Werner syndrome is a progeroid disorder characterized by premature age-related phenotypes. Although it is well established that autosomal recessive mutations in the WRN gene is responsible for Werner syndrome, the molecular alterations that lead to disease phenotype remain still unidentified.
Results: To address whether epigenetic changes can be associated with Werner syndrome phenotype, we analysed genome-wide DNA methylation profile using the Infinium MethylationEPIC BeadChip in the whole blood from three patients affected by Werner syndrome compared with three age- and sex-matched healthy controls. Read More
Several methods have been employed to measure telomere length (TL) in human studies. It has been difficult to directly compare the results from these studies because of differences in the laboratory techniques and output parameters. We compared TL measurements (TLMs) by the three most commonly used methods, quantitative polymerase chain reaction (qPCR), flow cytometry with fluorescence in situ hybridization (flow FISH) and Southern blot, in a cohort of patients with the telomere biology disorder dyskeratosis congenita (DC) and in their unaffected relatives (controls). Read More
Background: Children with inherited bone marrow failure syndromes (IBMFSs) may be symptomatic in utero, resulting in maternal and fetal problems during the pregnancy. Subsequent pregnancies by their mothers should be considered "high risk".
Methods: We retrospectively analyzed outcomes of 575 pregnancies in 165 unaffected mothers of offspring with Fanconi anemia (FA), dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), and Shwachman-Diamond syndrome (SDS) for events noted during pregnancy, labor, and delivery. Read More
Department of Chemistry and Biochemistry & Howard Hughes Medical Institute, University of Colorado, Boulder, CO - 80303, USA
Loss-of-function mutations in 3' -5' exoribonucleases have been implicated in hereditary human diseases. For example, PARN mutations cause a severe form of dyskeratosis congenita (DC), wherein PARN deficiency leads to human telomerase RNA instability. Since the DC phenotype in PARN patients is even more severe than loss-of-function alleles in telomerase components, we hypothesized that PARN would also be required for the stability of other RNAs. Read More
Stem Cell Reports 2017 Aug 27;9(2):409-418. Epub 2017 Jul 27.
Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Developmental Biology, Washington University in St. Louis, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA. Electronic address:
Dyskeratosis congenita (DC) is a bone marrow failure syndrome associated with telomere dysfunction. The progression and molecular determinants of hematopoietic failure in DC remain poorly understood. Here, we use the directed differentiation of human embryonic stem cells harboring clinically relevant mutations in telomerase to understand the consequences of DC-associated mutations on the primitive and definitive hematopoietic programs. Read More
Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; Retina Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts.
Hematol Oncol Stem Cell Ther 2017 Jun 15. Epub 2017 Jun 15.
Pediatric Hematology Oncology Section of Pediatric Stem Cell Transplant, Department of Pediatric Hematology Oncology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. Electronic address:
Bone marrow failure syndrome is an epithet of bone marrow failure (all or single-cell lineage) that is attributable to an underlying genetic aberration usually with a constellation of somatic abnormalities. Multiple inheritance patterns have been described in these disorders; many are transmitted in an autosomal recessive pattern, which may consequently lead to a higher prevalence of such illnesses in homogeneous societies such as Saudi Arabia, where consanguineous marriages are not uncommon. At King Faisal Specialist Hospital and Research Center, the most common entity referred for allogeneic hematopoietic cell transplantation (HCT) is Fanconi anemia, followed by pure red aplasia, and, less commonly, dyskeratosis congenita, congenital neutropenia, and others. Read More
The inherited marrow failure syndromes (IBMFS) are a heterogeneous group of diseases characterized by failure in the production of one or more blood lineage. The clinical manifestations of the IBMFS vary according to the type and number of blood cell lines involved, including different combinations of anemia, leukopenia, and thrombocytopenia. In some IBMFS, systemic non-hematologic manifestations, including congenital malformations, mucocutaneous abnormalities, developmental delay, and other medical complications, may be present. Read More
Hematopoietic stem cell transplantation (HSCT) using an optimized conditioning regimen is essential for the long-term survival of patients with inherited bone marrow failure syndromes (IBMFS). We report HSCT in 24 children with Fanconi anemia (FA, n = 12), Diamond-Blackfan anemia (DBA, n = 7), and dyskeratosis congenita (DC, n = 5) from a single HSCT center. The graft source was peripheral blood stem cells (n = 19) or cord blood stem cells (n = 5). Read More
DNA repair syndromes are heterogeneous disorders caused by pathogenic variants in genes encoding proteins key in DNA replication and/or the cellular response to DNA damage. The majority of these syndromes are inherited in an autosomal-recessive manner, but autosomal-dominant and X-linked recessive disorders also exist. The clinical features of patients with DNA repair syndromes are highly varied and dependent on the underlying genetic cause. Read More
Although bone marrow failure in patients with dyskeratosis congenita (DKC) can be successfully treated with allogeneic hematopoietic cell transplantation (allo-HCT) using a reduced intensity conditioning (RIC) regimen, the outcome of nonhematological disorders in patients with DKC treated with allo-HCT using RIC has not been fully elucidated. Here, we describe the clinical course of nonhematological disorders after allo-HCT with RIC in 3 consecutive patients with DKC. Allo-HCT with RIC was feasible in all cases; however, patient 1 developed lethal pulmonary disease and patient 2 experienced progression of hepatic fibrosis. Read More
Patients with inherited bone marrow failure syndromes (IBMFS), such as Fanconi anemia (FA), dyskeratosis congenita (DC), or Diamond Blackfan anemia (DBA), can have hematologic manifestations cured through hematopoietic cell transplantation (HCT). Subsequent late effects seen in these patients arise from a combination of the underlying disease, the pre-HCT therapy, and the HCT process. During the international consensus conference sponsored by the Pediatric Blood and Marrow Transplant Consortium on late effects screening and recommendations following allogeneic hematopoietic cell transplantation for immune deficiency and nonmalignant hematologic diseases held in Minneapolis, Minnesota in May 2016, a half-day session was focused specifically on the unmet needs for these patients with IBMFS. Read More
Typical features of dyskeratosis congenita (DC) resulting from excessive telomere shortening include bone marrow failure (BMF), mucosal fragility, and pulmonary or liver fibrosis. In more severe cases, immune deficiency and recurring infections can add to disease severity. RTEL1 deficiency has recently been described as a major genetic etiology, but the molecular basis and clinical consequences of RTEL1-associated DC are incompletely characterized. Read More
Background: The "hepatic factor," a molecule or group of molecules present in the hepatic venous blood, essential for the prevention of the development of pulmonary arteriovenous malformations (PAVMs) and right-to-left shunting has been a conceptual enigma in the understanding of many related conditions.
Methods: Patients with various forms of liver diseases including acute hepatic failure, and others with normal hepatic function like hereditary hemorrhagic telangiectasia (HHT), inflammatory and parasitic disorders, cardiogenic hepatopulmonary syndrome (cHPS) and skin disorders like Dyskeratosis congenita are all known to cause PAVMs. Over a period of the last two decades our understanding of the pathogenesis of PAVMs has changed, but the mechanisms are still not clearly understood. Read More
BackgroundPatients with inherited bone marrow failure syndromes (IBMFS) may have several risk factors for low bone mineral density (BMD). We aimed to evaluate the prevalence of low BMD in IBMFS and determine the associated risk factors.MethodsPatients with IBMFS with at least one dual-energy X-ray absorptiometry (DXA) scan were evaluated. Read More
Telomeres are repetitive ribonucleoprotein complexes present at ends of chromosomes. To synthesize this manuscript, a thorough literature search was done using PubMed, MEDLINE and Cochrane review for English-language literature and data available from the period of 2005-2016 were analyzed for manuscript writing. Telomeres help in maintaining the cellular health, inbuilt cellular mechanisms, metabolism and normal cell cycle. Read More
We developed a variant-annotation method that combines sequence-based machine-learning classification with a context-dependent algorithm for selecting splice variants. Our approach is distinctive in that it compares the splice potential of a sequence bearing a variant with the splice potential of the reference sequence. After training, classification accurately identified 168 of 180 (93. Read More
An 8-year-old girl who had experienced intermittent cough and fever over a 3 year period, was admitted after experiencing a recurrence for one month. One year ago the patient experienced a recurrent oral mucosal ulcer. Physical examination showed vitiligo in the skin of the upper right back. Read More
The poly-A specific ribonuclease (PARN), initially characterized for its role in mRNA catabolism, supports the processing of different types of non-coding RNAs including telomerase RNA. Mutations in PARN are linked to dyskeratosis congenita and pulmonary fibrosis. Here, we show that PARN is part of the enzymatic machinery that matures the human 18S ribosomal RNA (rRNA). Read More
Critical telomere shortening (for example, secondary to partial telomerase deficiency in the rare disease dyskeratosis congenita) causes tissue pathology, but underlying mechanisms are not fully understood. Mice lacking telomerase (for example, mTR(-/-) telomerase RNA template mutants) provide a model for investigating pathogenesis. In such mice, after several generations of telomerase deficiency telomeres shorten to the point of uncapping, causing defects most pronounced in high-turnover tissues including intestinal epithelium. Read More
Telomeres, the protective ends of linear chromosomes, shorten throughout an individual's lifetime. Telomere shortening is proposed to be a primary molecular cause of aging. Short telomeres block the proliferative capacity of stem cells, affecting their potential to regenerate tissues, and trigger the development of age-associated diseases. Read More
The inherited bone marrow failure syndromes (IBMFS) typically present with significant cytopenias in at least one haematopoietic cell lineage that may progress to pancytopenia, and are associated with increased risk of cancer. Although the clinical features of the IBMFS are often diagnostic, variable disease penetrance and expressivity may result in diagnostic dilemmas. The discovery of the genetic aetiology of the IBMFS has been greatly facilitated by next-generation sequencing methods. Read More
Naturally occurring mutations in the ribonucleoprotein reverse transcriptase, telomerase, are associated with the bone marrow failure syndromes dyskeratosis congenita, aplastic anemia, and idiopathic pulmonary fibrosis. However, the mechanism by which these mutations impact telomerase function remains unknown. Here we present the structure of the human telomerase C-terminal extension (or thumb domain) determined by the method of single-wavelength anomalous diffraction to 2. Read More
Background: Mutations in the long noncoding RNA RNase component of the mitochondrial RNA processing endoribonuclease (RMRP) give rise to the autosomal recessive condition cartilage-hair hypoplasia (CHH). The CHH disease phenotype has some overlap with dyskeratosis congenita, a well-known "telomere disorder." RMRP binds the telomerase reverse transcriptase (catalytic subunit) in some cell lines, raising the possibility that RMRP might play a role in telomere biology. Read More
Med Sci (Paris) 2017 Jan 25;33(1):95-98. Epub 2017 Jan 25.
Génétique de la suppression tumorale, Équipe Labellisée Ligue, Institut Curie, Centre de recherche, 26, rue d'Ulm, 75248 Paris Cedex 05, France - Sorbonne Universités, UPMC, Université Paris 6, Paris, France - CNRS UMR 3244, Paris, France - PSL Research University, Paris, France.
Fanconi anemia (FA), dyskeratosis congenita (DC), and Diamond Blackfan anemia (DBA) are 3 of the most common inherited bone marrow failure syndromes (IBMFS), in which the hematologic manifestations can be cured with hematopoietic cell transplantation (HCT). Later in life, these patients face a variety of medical conditions, which may be a manifestation of underlying disease or due to pre-HCT therapy, the HCT, or a combination of all these elements. Very limited long-term follow-up data exist in these populations, with FA the only IBMFS that has specific published data. Read More
Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Applied Cancer Research Pavillion, 3201 rue Jean-Mignault, Sherbrooke, Quebec, J1E 4K8, Canada. Electronic address:
Telomerase reverse transcriptase elongates telomeres to overcome their natural attrition and allow unlimited cellular proliferation, a characteristic shared by stem cells and the majority of malignant cancerous cells. The telomerase holoenzyme comprises a core RNA molecule, a catalytic protein subunit, and other accessory proteins. Malfunction of certain telomerase components can cause serious genetic disorders including dyskeratosis congenita and aplastic anaemia. Read More
Background: Revesz syndrome is a telomere disorder in the dyskeratosis congenita (DKC) spectrum characterized by exudative retinopathy, bone marrow failure, neuroradiographic abnormalities, and integumentary findings.
Materials/methods: We report the ophthalmologic findings, documented by examinations under anesthesia with clinical photography and fluorescein angiography, as well as the systemic manifestations and genetic and molecular testing, in identical twins with Revesz syndrome, and compare and contrast these features to those of other pediatric retinal vasculopathies.
Results: Both twins exhibited widespread avascularity and anomalous vasculature of the retinal periphery, retinal telangiectasias, and exudation. Read More
Dyskeratosis congenita (DC) is a rare inherited disease in which the telomere complex cannot be maintained. Shortened telomeres can cause a number of clinical conditions. We herein report a case of unrelated bone marrow transplantation due to aplastic anemia associated with DC. Read More
Dyskeratosis congenita (DC) is a very rare inherited disorder. It is caused by dysfunction of telomere maintenance. It involves RNA telomerase components relevant to various mutations leading to a classic triad of physical findings consisting of nail dystrophy of the hands and feet, mucosal leukoplakia, and reticular pigmentation of the skin, most commonly on the head, neck, and trunk. Read More
Dyskeratosis congenita (DC) is an inherited bone marrow failure and cancer susceptibility syndrome caused by germline mutations in telomere biology genes. Germline mutations in DKC1, which encodes the protein dyskerin, cause X-linked recessive DC. Because of skewed X-chromosome inactivation, female DKC1 mutation carriers do not typically develop clinical features of DC. Read More
The growing proportion of elderly people represents an increasing economic burden, not least because of age-associated diseases that pose a significant cost to the health service. Finding possible interventions to age-associated disorders therefore have wide ranging implications. A number of genetically defined accelerated aging diseases have been characterized that can aid in our understanding of aging. Read More
Telomerase replicates chromosome ends to facilitate continued cell division. Mutations that compromise telomerase function result in stem cell failure diseases, such as dyskeratosis congenita (DC). One such mutation (K170Δ), residing in the telomerase-recruitment factor TPP1, provides an excellent opportunity to structurally, biochemically, and genetically dissect the mechanism of such diseases. Read More
Dyskeratosis congenita (DC) is a rare inherited telomeropathy most frequently caused by mutations in a number of genes all thought to be involved in telomere maintenance. The main causes of mortality in DC are bone marrow failure as well as malignancies including leukemias and solid tumors. The clinical picture including the degree of bone marrow failure is highly variable and factors that contribute to this variability are poorly understood. Read More
Background: The inherited bone marrow failure syndromes (IBMFSs) are diverse disorders with syndrome-specific features; their otologic and audiologic manifestations have not been well described. Our objective was to characterize these in patients with Fanconi anemia (FA), dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), and Shwachman-Diamond syndrome (SDS), and to determine the association between physical findings and hearing loss.
Methods: Patients with an IBMFS underwent comprehensive clinical and laboratory evaluations and testing for syndrome-specific gene mutations. Read More
Telomere syndromes (syn. Telomeropathies) are inherited disorders hallmarked by accelerated telomere shortening based on a molecular defect within the telomerase/telomere complex. The rare, but well-defined model disorder Dyskeratosis congenita (DKC) characterized by typical skin manifestations and bone marrow failure represents the classical manifestation of telomere syndromes in childhood and adolescence. Read More
Purpose Of Review: Dyskeratosis congenita is an inherited bone marrow failure syndrome caused by defects in telomere maintenance. Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for bone marrow failure because of dyskeratosis congenita. The present review summarizes the literature with respect to the diagnosis and treatment of patients with dyskeratosis congenita who received HSCT, and discusses the recent progress in the management of dyskeratosis congenita. Read More
*Associated Retinal Consultants, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan; †Department of Neurology and Ophthalmology, Michigan State University, East Lansing, Michigan; ‡Department of Ophthalmology, Beaumont Hospital-Southshore Campus, Trenton, Michigan; §Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts; ¶Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; and **Florida Retina Institute, Jacksonville, Florida.
Dyskeratosis congenita is a highly pleotropic genetic disorder. This heterogeneity can lead to difficulties in making an accurate diagnosis and delays in appropriate management. The aim of this study was to determine the underlying genetic basis in patients presenting with features of dyskeratosis congenita and who were negative for mutations in the classical dyskeratosis congenita genes. Read More
Dyskeratosiscongenita (DKC) is a genetically heterogeneous disease of defective telomere maintenance that may demonstrate different patterns of inheritance. It is characterized by thetriad of dystrophy of the nails, leukokeratosis of the oral mucosa, and extensive net-like pigmentation of the skin. We report a case ofDKC who presented with a chief complaint of dysphagia. Read More
Cell Stem Cell 2016 Sep 18;19(3):397-405. Epub 2016 Aug 18.
Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Cell and Molecular Biology Program, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. Electronic address:
Patients with dyskeratosis congenita (DC) suffer from stem cell failure in highly proliferative tissues, including the intestinal epithelium. Few therapeutic options exist for this disorder, and patients are treated primarily with bone marrow transplantation to restore hematopoietic function. Here, we generate isogenic DC patient and disease allele-corrected intestinal tissue using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated gene correction in induced pluripotent stem cells and directed differentiation. Read More
Zinsser-Cole-Engmann syndrome also called Dyskeratosis Congenita (DKC) is a rare genodermatosis first described by Zinsser in 1906. Mutations in DKC1 gene is responsible for DKC. It is usually inherited as an X-linked recessive trait, resulting in a striking male predilection. Read More
Inherited bone marrow failure syndromes (IBMFS) are a heterogeneous group of genetic disorders characterized by bone marrow failure, congenital anomalies, and an increased risk of malignancies. Diagnosis is often difficult due to the wide variety of clinical expressions. The representative diseases are Diamond Blackfan anemia (DBA), Fanconi anemia (FA), congenital sideroblastic anemia (CSA), congenital dyserhthropoietic anemia, Shwachman Diamond syndrome, and dyskeratosis congenita. Read More