Single-gene mutations are important causes of congenital heart defects in children. Mutations in the gene have been recently described in the literature as a cause of septal defects and cardiomyopathy. However, the spectrum of cardiac disease associated with gene mutations is variable, ranging from asymptomatic septal defects to cardiomyopathy and sudden death.
View Article and Find Full Text PDFBackground: Protein metabolism and urea production maintain protein and amino acid homeostasis in normal status. Ammonia results from amino acid turnover and is produced by intestinal urease-positive bacteria. Ammonia must be detoxified, and the urea cycle converts ammonia into urea.
View Article and Find Full Text PDFIntroduction: This study addresses the rising cardiovascular disease (CVD) rates in the United Arab Emirates (UAE) by investigating the occurrence and impact of genetic variants in CVD-related genes.
Methods: We collected all genes linked to heritable CVD from public and diagnostic databases and mapped them to their corresponding biological processes and molecular pathways. We then evaluated the types and burden of genetic variants within these genes in 343 individuals from the Emirati Mendelian Study Cohort and 3,007 national electronic health records.
Background: NOTCH3 encodes a transmembrane receptor critical for vascular smooth muscle cell function. NOTCH3 variants are the leading cause of hereditary cerebral small vessel disease (SVD). While monoallelic cysteine-involving missense variants in NOTCH3 are well-studied in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), patients with biallelic variants in NOTCH3 are extremely rare and not well characterised.
View Article and Find Full Text PDFTransaldolase deficiency is a rare autosomal recessive inborn error of carbohydrate metabolism caused by pathogenic/likely pathogenic biallelic mutations in the gene. This disorder is characterized by multisystem involvement with variable phenotypes, including intrauterine growth restriction; dysmorphic features; abnormal skin; hepatosplenomegaly; cytopenia; and cardiac, renal, and endocrine abnormalities. Herein, we present two Emirati patients with hypergonadotropic hypogonadism due to transaldolase deficiency and variable phenotypes of systemic involvement.
View Article and Find Full Text PDFMED27 is a subunit of the Mediator multiprotein complex, which is involved in transcriptional regulation. Biallelic MED27 variants have recently been suggested to be responsible for an autosomal recessive neurodevelopmental disorder with spasticity, cataracts and cerebellar hypoplasia. We further delineate the clinical phenotype of MED27-related disease by characterizing the clinical and radiological features of 57 affected individuals from 30 unrelated families with biallelic MED27 variants.
View Article and Find Full Text PDFJ Investig Med High Impact Case Rep
June 2023
Porphyrias, particularly acute intermittent porphyria (AIP), are rare, inherited disorders of heme synthesis. On the other hand, systemic lupus erythematosus (SLE) is an uncommon autoimmune disease that affects women predominantly. The coexistence of AIP and SLE is rare.
View Article and Find Full Text PDFMol Genet Genomic Med
November 2022
Background: Hearing loss (HL) is a heterogeneous condition that causes partial or complete hearing impairment. Hundreds of variants in >60 genes have been reported to be associated with Hereditary HL (HHL), variants of the GJB2 gene are the most common cause of congenital SNHL, with >100 variants reported. The HHL prevalence is thought to be high in the Arab population; however, the genetic epidemiology of HHL among Emirati populations is understudied.
View Article and Find Full Text PDFEndocrinol Diabetes Metab Case Rep
September 2022
Summary: The most frequent causes of pancreatitis classically have been known to be gallstones or alcohol. However, genetics can also play a key role in predisposing patients to both chronic and acute pancreatitis. The serine protease inhibitor Kazal type 1 (SPINK 1) gene is known to be strongly associated with pancreatitis.
View Article and Find Full Text PDFPurpose: The mediator (MED) multisubunit-complex modulates the activity of the transcriptional machinery, and genetic defects in different MED subunits (17, 20, 27) have been implicated in neurologic diseases. In this study, we identified a recurrent homozygous variant in MED11 (c.325C>T; p.
View Article and Find Full Text PDFPontocerebellar hypoplasia type 9 (PCH-9) is a very rare autosomal recessive neurodegenerative disorder. Affected infants present early with severe developmental delay, spasticity, with the unique magnetic resonance imaging picture of thin corpus callosum, atrophied pons, and cerebellum. It is caused by loss of function mutations in the gene, encoding for the adenosine monophosphate deaminase enzyme-paralog 2.
View Article and Find Full Text PDFBackground: The discovery of coding variants in genes that confer risk of intellectual disability (ID) is an important step toward understanding the pathophysiology of this common developmental disability.
Methods: Homozygosity mapping, whole-exome sequencing, and cosegregation analyses were used to identify gene variants responsible for syndromic ID with autistic features in two independent consanguineous families from the Arabian Peninsula. For in vivo functional studies of the implicated gene's function in cognition, Drosophila melanogaster and mice with targeted interference of the orthologous gene were used.
Here, we delineate the phenotype of two siblings with a bi-allelic frameshift variant in MMP15 gene with congenital cardiac defects, cholestasis, and dysmorphism. Genome sequencing analysis revealed a recently reported homozygous frameshift variant (c.1058delC, p.
View Article and Find Full Text PDFThe variants of electron transfer flavoprotein (, ) and ETF dehydrogenase () are the leading cause of glutaric aciduria type II (GA-II). In this study, we identified 13 patients harboring six variants of two genes associated with GA-II. Out of the six variants, four were missense, and two were frameshift mutations.
View Article and Find Full Text PDFClinical and molecular characterization of neuro-genetic disorders among UAE national patients seen in the Genetic Clinic at Tawam hospital over a period of 3 years. A retrospective chart review of all Emirati patients assessed by clinical geneticists due to neuro-genetic disorders including global developmental delay, ASD, ID, ADHD, and epilepsy in combination with abnormalities of other organ systems. Each patient had proper assessment including detailed history, three-generation family history, developmental history and detailed physical examination looking for other system involvement.
View Article and Find Full Text PDFPurpose: Within this study, we aimed to discover novel gene-disease associations in patients with no genetic diagnosis after exome/genome sequencing (ES/GS).
Methods: We followed two approaches: (1) a patient-centered approach, which after routine diagnostic analysis systematically interrogates variants in genes not yet associated to human diseases; and (2) a gene variant centered approach. For the latter, we focused on de novo variants in patients that presented with neurodevelopmental delay (NDD) and/or intellectual disability (ID), which are the most common reasons for genetic testing referrals.
Hereditary orotic aciduria (HOA) is a very rare inborn error of pyrimidine metabolism. It results from a defect of the uridine-5-monophosphate synthase () gene. To date, only about twenty patients have been described.
View Article and Find Full Text PDFBackground: Disorders of sex development (DSD) can result from congenital defect in sex determining pathway. Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) is one of the commonest genes that has been identified to cause 46, XY DSD. It can present as complete or partial gonadal dysgenesis even within the same kindred.
View Article and Find Full Text PDFDespite clear technical superiority of genome sequencing (GS) over other diagnostic methods such as exome sequencing (ES), few studies are available regarding the advantages of its clinical application. We analyzed 1007 consecutive index cases for whom GS was performed in a diagnostic setting over a 2-year period. We reported pathogenic and likely pathogenic (P/LP) variants that explain the patients' phenotype in 212 of the 1007 cases (21.
View Article and Find Full Text PDFSpastic tetraplegia, thin corpus callosum, and progressive microcephaly is a recently described very rare autosomal recessive neurodevelopmental disorder. This disease was first described in 2015 in several families from the Ashkenazi Jewish ancestry with a founder mutation in (p.E256K) as the underlying genetic cause.
View Article and Find Full Text PDFIntellectual disability (ID) is one of the most common developmental disorders characterized by a congenital limitation in intellectual functioning and adaptive behavior. More than 800 genes have been implicated so far in the pathogenesis of syndromic and non-syndromic ID conditions with the actual number is expected to be over two thousand. The advent of next-generation sequencing resulted in the identification of many novel ID genes with new genes are being reported on weekly basis.
View Article and Find Full Text PDFSchindler disease is a rare autosomal recessive lysosomal storage disorder caused by a deficiency in alpha-N-acetylgalactosaminidase (α-NAGA) activity due to defects in the NAGA gene. Accumulation of the enzyme's substrates results in clinically heterogeneous symptoms ranging from asymptomatic individuals to individuals with severe neurological manifestations. Here, a 5-year-old Emirati male born to consanguineous parents presented with congenital microcephaly and severe neurological manifestations.
View Article and Find Full Text PDF