HECT And RLD Domain-Containing E3 Ubiquitin Protein Ligase 2, or HERC2, codes an ubiquitin ligase that has an important role in key cellular processes including cell cycle regulation, DNA repair, mitochondrial functions, and spindle formation during mitosis. While HERC2 Neurodevelopmental Disorder in Old Order Amish is a well characterized human disorder involving HERC2, bi-allelic HERC2 loss of function has only been described in three families and results in a more severe neurodevelopmental disorder. Herein, we delineate the HERC2 loss of function phenotype by describing three previously unreported patients, and by summarizing the molecular and phenotypic information of all known HERC2 missense variants and biallelic loss of function patients.
View Article and Find Full Text PDFA subset of a larger and heterogeneous class of disorders, the congenital myasthenic syndromes (CMS) are caused by pathogenic variants in genes encoding proteins that support the integrity and function of the neuromuscular junction (NMJ). A central component of the NMJ is the sodium-dependent high-affinity choline transporter 1 (CHT1), a solute carrier protein (gene symbol SLC5A7), responsible for the reuptake of choline into nerve termini has recently been implicated as one of several autosomal recessive causes of CMS. We report the identification and functional characterization of a novel pathogenic variant in SLC5A7, c.
View Article and Find Full Text PDFObjectives: To estimate the prevalence of childhood permanent hearing loss (PHL) after early cardiac surgery.
Study Design: This prospective observational (1996-2015) study after complex cardiac surgery with cardiopulmonary bypass at ≤6 weeks of life reports audiology follow-up by registered pediatric-experienced audiologists at 6-8 months postsurgery, age 2 years, and as required throughout and thereafter to complete diagnoses. PHL at any frequency (500-4000 Hz) is defined as responses of >25-decibel hearing level in either ear.
Background: Congenital central hypoventilation syndrome (CCHS) is a rare life-threatening disorder of respiratory and autonomic regulation. It is classically caused by dominant mutations in the transcription factor . The objective of the present study was to identify the molecular cause of a recessive form of central hypoventilation with autonomic dysfunction.
View Article and Find Full Text PDFObjective: This guideline was written to update Canadian maternity care and reproductive healthcare providers on pre- and postconceptional reproductive carrier screening for women or couples who may be at risk of being carriers for autosomal recessive (AR), autosomal dominant (AD), or X-linked (XL) conditions, with risk of transmission to the fetus. Four previous SOGC- Canadian College of Medical Geneticists (CCMG) guidelines are updated and merged into the current document.
Intended Users: All maternity care (most responsible health provider [MRHP]) and paediatric providers; maternity nursing; nurse practitioner; provincial maternity care administrator; medical student; and postgraduate resident year 1-7.
Circumferential skin creases Kunze type (CSC-KT) is a specific congenital entity with an unknown genetic cause. The disease phenotype comprises characteristic circumferential skin creases accompanied by intellectual disability, a cleft palate, short stature, and dysmorphic features. Here, we report that mutations in either MAPRE2 or TUBB underlie the genetic origin of this syndrome.
View Article and Find Full Text PDFJ Pediatr Endocrinol Metab
March 2020
We describe four phenotypically different brothers who share the same microduplication of Xq27.1, which contains the SOX3 gene. SOX3 mutations have been associated with growth hormone deficiency, variable degrees of additional pituitary hormone deficiencies, and mental retardation.
View Article and Find Full Text PDFMiller-Dieker syndrome (MDS) is a rare genetic syndrome associated with lissencephaly, developmental delay, and high mortality. We describe a patient who was diagnosed postnatally with both MDS and congenital lobar emphysema. We believe that this is the first reported case of the two conditions presenting in the same patient.
View Article and Find Full Text PDFBackground: Isolated central congenital hypothyroidism (ICCH) is rare but important. Most ICCH patients are diagnosed later, which results in severe growth failure and intellectual disability.
Objective: We describe a boy with ICCH due to a large homozygous TSHβ gene deletion.
IMPORTANCE Diprosopus is a medical condition that refers to full or partial craniofacial duplication. A particular subset of this condition, duplication of the mouth, is an exceedingly rare condition, with 7 reported cases in the medical literature. The embryogenesis and mechanism of disease are not well understood.
View Article and Find Full Text PDFDyskeratosis congenita and its variants have overlapping phenotypes with many disorders including Coats plus, and their underlying pathology is thought to be one of defective telomere maintenance. Recently, biallelic CTC1 mutations have been described in patients with syndromes overlapping Coats plus. CTC1, STN1 and TEN1 are part of the telomere-capping complex involved in maintaining telomeric structural integrity.
View Article and Find Full Text PDFCostello syndrome was delineated based on its distinctive phenotype including severe failure-to-thrive with macrocephaly, characteristic facial features, hypertrophic cardiomyopathy, papillomata, malignant tumors, and cognitive impairment. Heterozygous germline mutations in the proto-oncogene HRAS cause Costello syndrome, and its inheritance pattern would thus be autosomal dominant. With exception of two instances of parental mosaicism, one presumed gonadal and the other proven somatic mosaicism for the p.
View Article and Find Full Text PDFThe recurrence of cerebral palsy in the same family is uncommon. We, however, report on two families with two or more affected siblings. In both families, numerous potential risk factors were identified including environmental, obstetric, and possible maternal effects.
View Article and Find Full Text PDFObjective: This study determined neurodevelopmental outcomes of survivors of neonatal cardiac surgery for interrupted aortic arch through an interprovincial program and explored preoperative, intraoperative, and postoperative outcome predictors.
Methods: Children who underwent neonatal cardiac surgery for interrupted aortic arch at 6 weeks old or younger between 1996 and 2006 had a multidisciplinary neurodevelopmental assessment at 18 to 24 months old (mental and psychomotor developmental indices as mean +/- SD and delay [score <70]). Survivor outcomes were compared by univariate and multivariate analyses and compared between children with and without chromosomal abnormality.
Costello syndrome is a rare congenital disorder typically characterized by severe failure-to-thrive, cardiac abnormalities including tachyarrhythmia and hypertrophic cardiomyopathy, distinctive facial features, a predisposition to papillomata and malignant tumors, neurologic abnormalities, developmental delay, and mental retardation. Its underlying cause is de novo germline mutations in the oncogene HRAS. Almost all Costello syndrome mutations affect one of the glycine residues in position 12 or 13 of the protein product.
View Article and Find Full Text PDFCowden disease (also known as Cowden syndrome) is characterized by multiple organ hamartomatous tumors and an increased risk of malignancy, in particular of the breast, thyroid and endometrium. Testicular tumors including seminoma have previously been reported in adult patients. We are reporting, for the first time, a case of testicular mixed germ cell tumor in an adolescent with Cowden disease.
View Article and Find Full Text PDFWe describe a patient with facioscapulohumeral muscular dystrophy (FSHD) associated with Möbius syndrome and congenital ophthalmoplegia. This 7-year-old girl had profound limitation of extraocular movements since birth, congenital facial diplegia, neonatal hypotonia, and progressive limb-girdle weakness. FSHD genetic testing revealed a pathogenic haplotype with a D4Z4 repeat of 30 kb.
View Article and Find Full Text PDFObjective: Neonatal complex cardiac surgery carries a significant risk for adverse neurodevelopmental outcome. We hypothesized this risk to be higher in patients with deletion 22q11.2.
View Article and Find Full Text PDFWe describe two brothers with bilateral exudative retinopathy, intracranial calcifications, a sclerotic bony disorder, and normal intelligence. The younger brother also has osteopenia, mild splenomegaly, and pancytopenia. We review the literature with emphasis on the unique features of these patients.
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