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Journal of Medical Genetics Sep 1974The tricho-rhino-phalangeal syndrome is characterized by sparse fine hair, bulbous nose, and brachydactyly. The clinical and radiological findings of four affected...
The tricho-rhino-phalangeal syndrome is characterized by sparse fine hair, bulbous nose, and brachydactyly. The clinical and radiological findings of four affected family members, a father and his three children, are presented. Cardiovascular anomalies, previously unreported in this syndrome, were present in one of the children. Psychological and immunological evaluations were found to be essentially normal. The genetics of this condition and suggested counselling are presented.
Topics: Adult; Child; Fingers; Genes, Dominant; Hair; Heart Septal Defects, Atrial; Humans; Male; Nose Deformities, Acquired; Pedigree; Radiography; Syndrome
PubMed: 4431036
DOI: 10.1136/jmg.11.3.312 -
Current Hypertension Reviews 2020Advances in molecular research techniques have enabled a new frontier in discerning the mechanisms responsible for monogenic diseases. In this review, we discuss the... (Review)
Review
Advances in molecular research techniques have enabled a new frontier in discerning the mechanisms responsible for monogenic diseases. In this review, we discuss the current research on the molecular pathways governing blood pressure disorders with a Mendelian inheritance pattern, each presenting with a unique pathophysiology. Glucocorticoid Remediable Aldosteronism (GRA) and Apparent Mineralocorticoid Excess (AME) are caused by mutations in regulatory enzymes that induce increased production of mineralocorticoids or inhibit degradation of glucocorticoids, respectively. Geller syndrome is due to a point mutation in the hormone responsive element of the promotor for the mineralocorticoid receptor, rendering the receptor susceptible to activation by progesterone, leading to hypertension during pregnancy. Pseudohypoaldosteronism type II (PHA-II), also known as Gordon's syndrome or familial hyperkalemic hypertension, is a more variable disorder typically characterized by hypertension, high plasma potassium and metabolic acidosis. Mutations in a variety of intracellular enzymes that lead to enhanced sodium reabsorption have been identified. In contrast, hypertension in Liddle's syndrome, which results from mutations in the Epithelial sodium Channel (ENaC), is associated with low plasma potassium and metabolic alkalosis. In Liddle's syndrome, truncation of one the ENaC protein subunits removes a binding site necessary protein for ubiquitination and degradation, thereby promoting accumulation along the apical membrane and enhanced sodium reabsorption. The myriad effects due to mutation in phosphodiesterase 3A (PDE3A) lead to severe hypertension underlying sodium-independent autosomal dominant hypertension with brachydactyly. How mutations in PDE3A result in the phenotypic features of this disorder are discussed. Understanding the pathologies of these monogenic hypertensive disorders may provide insight into the causes of the more prevalent essential hypertension and new avenues to unravel the complexities of blood pressure regulation.
Topics: Blood Pressure; Genetic Predisposition to Disease; Heredity; Humans; Hypertension; Inheritance Patterns; Mutation; Pedigree; Phenotype; Prognosis; Risk Factors
PubMed: 30963979
DOI: 10.2174/1573402115666190409115330 -
Frontiers in Genetics 2020Epigenetic processes are critical for governing the complex spatiotemporal patterns of gene expression in neurodevelopment. One such mechanism is the dynamic network of... (Review)
Review
Epigenetic processes are critical for governing the complex spatiotemporal patterns of gene expression in neurodevelopment. One such mechanism is the dynamic network of post-translational histone modifications that facilitate recruitment of transcription factors or even directly alter chromatin structure to modulate gene expression. This is a tightly regulated system, and mutations affecting the function of a single histone-modifying enzyme can shift the normal epigenetic balance and cause detrimental developmental consequences. In this review, we will examine select neurodevelopmental conditions that arise from mutations in genes encoding enzymes that regulate histone methylation and acetylation. The methylation-related conditions discussed include Wiedemann-Steiner, Kabuki, and Sotos syndromes, and the acetylation-related conditions include Rubinstein-Taybi, KAT6A, genitopatellar/Say-Barber-Biesecker-Young-Simpson, and brachydactyly mental retardation syndromes. In particular, we will discuss the clinical/phenotypic and genetic basis of these conditions and the model systems that have been developed to better elucidate cellular and systemic pathological mechanisms.
PubMed: 33488679
DOI: 10.3389/fgene.2020.613098 -
BMC Pediatrics Sep 2022Brachydactyly type B is an autosomal dominant disorder that is characterized by hypoplasia of the distal phalanges and nails and can be divided into brachydactyly type...
BACKGROUND
Brachydactyly type B is an autosomal dominant disorder that is characterized by hypoplasia of the distal phalanges and nails and can be divided into brachydactyly type B1 (BDB1) and brachydactyly type B2 (BDB2). BDB1 is the most severe form of brachydactyly and is caused by truncating variants in the receptor tyrosine kinase-like orphan receptor 2 (ROR2) gene.
CASE PRESENTATION
Here, we report a five-generation Chinese family with brachydactyly with or without syndactyly. The proband and her mother underwent digital separation in syndactyly, and the genetic analyses of the proband and her parents were provided. The novel heterozygous frameshift variant c.1320dupG, p.(Arg441Alafs*18) in the ROR2 gene was identified in the affected individuals by whole-exome sequencing and Sanger sequencing. The c.1320dupG variant in ROR2 is predicted to produce a truncated protein that lacks tyrosine kinase and serine/threonine- and proline-rich structures and remarkably alters the tertiary structures of the mutant ROR2 protein.
CONCLUSION
The c.1320dupG, p.(Arg441Alafs*18) variant in the ROR2 gene has not been reported in any databases thus far and therefore is novel. Our study extends the gene variant spectrum of brachydactyly and may provide information for the genetic counselling of family members.
Topics: Brachydactyly; Carpal Bones; Female; Foot Deformities, Congenital; Hand Deformities, Congenital; Humans; Pedigree; Receptor Tyrosine Kinase-like Orphan Receptors; Stapes; Syndactyly; Synostosis; Tarsal Bones
PubMed: 36064339
DOI: 10.1186/s12887-022-03564-z -
Journal of Medical Genetics Oct 1994We report a multiple congenital anomalies (MCA) syndrome in three unrelated fetuses consisting of extremely thin, dense, fishbone-like diaphyses, flared metaphyses, mild...
We report a multiple congenital anomalies (MCA) syndrome in three unrelated fetuses consisting of extremely thin, dense, fishbone-like diaphyses, flared metaphyses, mild micromelic dwarfism, brachydactyly, facial dysmorphism, ocular malformations (microphthalmia, aniridia), cloverleaf skull deformity, and splenic hypoplasia. Histopathological investigations showed abnormalities of the metaphyseal cartilage and adjacent diaphyseal ossification, excessive modelling of the metaphyses, and, in one case, dysplasia of the epiphyseal cartilage. We review three previously reported cases. We suggest the name osteocraniostenosis to describe this radiological and clinical disorder, pinpointing its major clinical and radiological features.
Topics: Abnormalities, Multiple; Abortion, Induced; Adult; Face; Facial Bones; Female; Humans; Infant, Newborn; Male; Pregnancy; Radiography; Skull
PubMed: 7837254
DOI: 10.1136/jmg.31.10.772 -
European Journal of Endocrinology Jun 2013Notch receptors are single-pass transmembrane proteins that determine cell fate. Upon Notch ligand interactions, proteolytic cleavages release the Notch intracellular... (Review)
Review
Notch receptors are single-pass transmembrane proteins that determine cell fate. Upon Notch ligand interactions, proteolytic cleavages release the Notch intracellular domain, which translocates to the nucleus to regulate the transcription of target genes, including Hairy enhancer of split (Hes) and Hes related to YRPW motif (Hey). Notch is critical for skeletal development and activity of skeletal cells, and dysregulation of Notch signaling is associated with human diseases affecting the skeleton. Inherited or sporadic mutations in components of the Notch signaling pathway are associated with spondylocostal dysostosis, spondylothoracic dysostosis and recessive brachydactyly, diseases characterized by skeletal patterning defects. Inactivating mutations of the Notch ligand JAG1 or of NOTCH2 are associated with Alagille syndrome, and activating mutations in NOTCH2 are associated with Hajdu-Cheney syndrome (HCS). Individuals affected by HCS exhibit osteolysis in distal phalanges and osteoporosis. NOTCH is activated in selected tumors, such as osteosarcoma, and in breast cancer cells that form osteolytic bone metastases. In conclusion, Notch regulates skeletal development and bone remodeling, and gain- or loss-of-function mutations of Notch signaling result in important skeletal diseases.
Topics: Animals; Bone Remodeling; Bone and Bones; Humans; Receptors, Notch; Signal Transduction
PubMed: 23554451
DOI: 10.1530/EJE-13-0115 -
American Journal of Medical Genetics.... Sep 2020Saul-Wilson syndrome (SWS) is a rare autosomal recessive disorder characterized by microcephalic primordial dwarfism, spondyloepimetaphyseal dysplasia, characteristic...
Saul-Wilson syndrome (SWS) is a rare autosomal recessive disorder characterized by microcephalic primordial dwarfism, spondyloepimetaphyseal dysplasia, characteristic facial findings, clubfoot, brachydactyly, bilateral cataracts, and hearing loss. Recently, recurrent mutations in COG4, encoding a component of the Conserved Oligomeric Golgi (COG) complex, were identified. We created detailed growth curves for stature, weight, and head circumference, as well as weight-for-length and weight velocity charts for younger children, derived from hundreds of data points obtained by retrospective chart review from 14 individuals with molecularly-confirmed SWS. In addition, we performed statistical comparisons of height-for-age model fits before and after initiation of growth hormone supplementation, and found that this therapy does not appear to influence height in individuals with SWS. We hope that these charts will represent valuable tools for clinicians, both in assessing whether SWS seems an appropriate diagnosis, as well as to monitor growth of affected individuals. In particular, we hope that our detailed growth characterization will reduce morbidity resulting from unnecessarily aggressive nutritional interventions by well-intentioned physicians trying to promote weight gain, an unrealistic goal in this genetically-determined cause of primordial dwarfism.
Topics: Adolescent; Adult; Body Height; Child; Child, Preschool; Clubfoot; Dwarfism; Facies; Female; Fetal Growth Retardation; Humans; Infant; Infant, Newborn; Male; Microcephaly; Mutation; Osteochondrodysplasias; Vesicular Transport Proteins; Young Adult
PubMed: 32652690
DOI: 10.1002/ajmg.a.61754 -
Journal of Cardiovascular Development... Feb 2018A-kinase anchoring proteins (AKAPs) and cyclic nucleotide phosphodiesterases (PDEs) are essential enzymes in the cyclic adenosine 3'-5' monophosphate (cAMP) signaling... (Review)
Review
A-kinase anchoring proteins (AKAPs) and cyclic nucleotide phosphodiesterases (PDEs) are essential enzymes in the cyclic adenosine 3'-5' monophosphate (cAMP) signaling cascade. They establish local cAMP pools by controlling the intensity, duration and compartmentalization of cyclic nucleotide-dependent signaling. Various members of the AKAP and PDE families are expressed in the cardiovascular system and direct important processes maintaining homeostatic functioning of the heart and vasculature, e.g., the endothelial barrier function and excitation-contraction coupling. Dysregulation of AKAP and PDE function is associated with pathophysiological conditions in the cardiovascular system including heart failure, hypertension and atherosclerosis. A number of diseases, including autosomal dominant hypertension with brachydactyly (HTNB) and type I long-QT syndrome (LQT1), result from mutations in genes encoding for distinct members of the two classes of enzymes. This review provides an overview over the AKAPs and PDEs relevant for cAMP compartmentalization in the heart and vasculature and discusses their pathophysiological role as well as highlights the potential benefits of targeting these proteins and their protein-protein interactions for the treatment of cardiovascular diseases.
PubMed: 29461511
DOI: 10.3390/jcdd5010014 -
The Journal of Pathology Jan 2019Bone morphogenetic proteins (BMPs) are secreted cytokines that were initially discovered on the basis of their ability to induce bone. Several decades of research have... (Review)
Review
Bone morphogenetic proteins (BMPs) are secreted cytokines that were initially discovered on the basis of their ability to induce bone. Several decades of research have now established that these proteins function in a large variety of physiopathological processes. There are about 15 BMP family members, which signal via three transmembrane type II receptors and four transmembrane type I receptors. Mechanistically, BMP binding leads to phosphorylation of the type I receptor by the type II receptor. This activated heteromeric complex triggers intracellular signaling that is initiated by phosphorylation of receptor-regulated SMAD1, 5, and 8 (also termed R-SMADs). Activated R-SMADs form heteromeric complexes with SMAD4, which engage in specific transcriptional responses. There is convergence along the signaling pathway and, besides the canonical SMAD pathway, BMP-receptor activation can also induce non-SMAD signaling. Each step in the pathway is fine-tuned by positive and negative regulation and crosstalk with other signaling pathways. For example, ligand bioavailability for the receptor can be regulated by ligand-binding proteins that sequester the ligand from interacting with receptors. Accessory co-receptors, also known as BMP type III receptors, lack intrinsic enzymatic activity but enhance BMP signaling by presenting ligands to receptors. In this review, we discuss the role of BMP receptor signaling and how corruption of this pathway contributes to cardiovascular and musculoskeletal diseases and cancer. We describe pharmacological tools to interrogate the function of BMP receptor signaling in specific biological processes and focus on how these agents can be used as drugs to inhibit or activate the function of the receptor, thereby normalizing dysregulated BMP signaling. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Topics: Animals; Bone Morphogenetic Protein Receptors; Bone Morphogenetic Proteins; Cardiovascular Diseases; Humans; Ligands; Musculoskeletal Diseases; Neoplasms; Phosphorylation; Signal Transduction; Smad Proteins, Receptor-Regulated
PubMed: 30246251
DOI: 10.1002/path.5170 -
Journal of Clinical Research in... Dec 2017Disorders related to parathyroid hormone (PTH) resistance and PTH signaling pathway impairment are historically classified under the term of pseudohypoparathyroidism... (Review)
Review
Disorders related to parathyroid hormone (PTH) resistance and PTH signaling pathway impairment are historically classified under the term of pseudohypoparathyroidism (PHP). The disease was first described and named by Fuller Albright and colleagues in 1942. Albright hereditary osteodystrophy (AHO) is described as an associated clinical entity with PHP, characterized by brachydactyly, subcutaneous ossifications, round face, short stature and a stocky build. The classification of PHP is further divided into PHP-Ia, pseudo-PHP (pPHP), PHP-Ib, PHP-Ic and PHP-II according to the presence or absence of AHO, together with an in vivo response to exogenous PTH and the measurement of Gsα protein activity in peripheral erythrocyte membranes in vitro. However, PHP classification fails to differentiate all patients with different clinical and molecular findings for PHP subtypes and classification become more complicated with more recent molecular characterization and new forms having been identified. So far, new classifications have been established by the EuroPHP network to cover all disorders of the PTH receptor and its signaling pathway. Inactivating PTH/PTH-related protein signaling disorder (iPPSD) is the new name proposed for a group of these disorders and which can be further divided into subtypes - iPPSD1 to iPPSD6. These are termed, starting from PTH receptor inactivation mutation (Eiken and Blomstrand dysplasia) as iPPSD1, inactivating Gsα mutations (PHP-Ia, PHP-Ic and pPHP) as iPPSD2, loss of methylation of GNAS DMRs (PHP-Ib) as iPPSD3, PRKAR1A mutations (acrodysostosis type 1) as iPPSD4, PDE4D mutations (acrodysostosis type 2) as iPPSD5 and PDE3A mutations (autosomal dominant hypertension with brachydactyly) as iPPSD6. iPPSDx is reserved for unknown molecular defects and iPPSDn+1 for new molecular defects which are yet to be described. With these new classifications, the aim is to clarify the borders of each different subtype of disease and make the classification according to molecular pathology. The iPPSD group is designed to be expandable and new classifications will readily fit into it as necessary.
Topics: Chromogranins; GTP-Binding Protein alpha Subunits, Gs; Humans; Parathyroid Hormone; Parathyroid Hormone-Related Protein; Pseudohypoparathyroidism; Signal Transduction
PubMed: 29280743
DOI: 10.4274/jcrpe.2017.S006