Single-center experience of N-linked Congenital Disorders of Glycosylation with a Summary of Molecularly Characterized Cases in Arabs.

Congenital disorders of glycosylation (CDG) represent an expanding group of conditions that result from defects in protein and lipid glycosylation. Different subgroups of CDG display considerable clinical and genetic heterogeneity due to the highly complex nature of cellular glycosylation. This is further complicated by ethno-geographic differences in the mutational landscape of each of these subgroups. Ten Arab CDG patients from Latifa Hospital in Dubai, United Arab Emirates, were assessed using biochemical (glycosylation status of transferrin) and molecular approaches (next-generation sequencing [NGS] and Sanger sequencing). In silico tools including CADD and PolyPhen-2 were used to predict the functional consequences of uncovered mutations. In our sample of patients, five novel mutations were uncovered in the genes: MPDU1, PMM2, MAN1B1, and RFT1. In total, 9 mutations were harbored by the 10 patients in 7 genes. These are missense and nonsense mutations with deleterious functional consequences. This article integrates a single-center experience within a list of reported CDG mutations in the Arab world, accompanied by full molecular and clinical details pertaining to the studied cases. It also sheds light on potential ethnic differences that were not noted before in regards to CDG in the Arab world.

Identification of a novel homozygous UNC80 variant in a child with infantile hypotonia with psychomotor retardation and characteristic facies-2 (IHPRF2).

The UNC80 gene encodes for a large component of the NALCN sodium-leak channel complex that regulates the basal excitability of the nervous system. In this study, we report on a novel homozygous mutation in UNC80 in a Palestinian-Emirati patient suffering infantile hypotonia with psychomotor retardation and characteristic facies. This mutation was detected by whole exome sequencing and confirmed using Sanger sequencing in the patient-parents trio. Numerous elements in the patient's phenotype were in agreement with the few reported cases of UNC80 mutations; however there are some notable differences. We present comprehensive clinical and molecular accounts of this mutation in addition to a full review of previously reported patients of UNC80 mutations.

Identification of a novel CTCF mutation responsible for syndromic intellectual disability - a case report.

BACKGROUND: Autosomal dominant mental retardation 21 (MRD21) is a very rare condition, characterized by short stature, microcephaly, mild facial dysmorphisms and intellectual disability that ranged from mild to severe. MRD21 is caused by mutations in CCCTC-binding factor (CTCF) and this was established through only four unrelated cases, two of which had frameshift mutations. CTCF is a master transcriptional regulator that controls chromatin structure and may serve as insulator and transcriptional activator and repressor. CASE PRESENTATION: This study presents, clinically and molecularly, an Emirati patient with de novo frameshift mutation in CTCF. This novel mutation was uncovered using whole exome sequencing and was confirmed by Sanger sequencing in the trio. In silico analysis, using SIFT Indel, indicates that this frameshift; p.Lys206Profs*13 is functionally damaging with the likely involvement of nonsense-mediated mRNA decay. CONCLUSIONS: Upon comparing the clinical picture of the herewith-reported individual with previously reported cases of MRD21, there seems to be many common symptoms, and few new ones that were not observed before. This helps to further define this rare condition and its molecular underpinnings.

A novel, putatively null, FGD1 variant leading to Aarskog-Scott syndrome in a family from UAE.

BACKGROUND: The X-linked condition "Aarskog-Scott syndrome (AAS)" causes a characteristic combination of short stature, facial, genital and skeletal anomalies. Studies elucidated a causative link between AAS and mutations in the FGD1 gene, which encodes a Rho/Rac guanine exchange factor. FGD1 is involved in regulating signaling pathways that control cytoskeleton organization and embryogenesis. CASE PRESENTATION: FGD1 was studied in an Emirati family with two cases of AAS using PCR amplification and direct sequencing of the entire coding region of the gene. Various in silico tools were also used to predict the functional consequences of FGD1 mutations. In the reported family, two brothers harbor a novel hemizygous mutation in FGD1 c.53del (p.Pro18Argfs*106) for which the mother is heterozygous. This frameshift deletion, being close to N-terminus of FGD1, is predicted to shift the reading frame in a way that it translates to 105 erroneous amino acids followed by a premature stop codon at position 106. Full molecular and clinical accounts about the variant are given so as to expand molecular and phenotypical knowledge about this disorder. CONCLUSIONS: A novel variant in FGD1 was found in an Emirati family with two brothers suffering from AAS. The variant is predicted to be a null mutation, and this is the first report of its kind from the United Arab Emirates.

A Novel Variant in the Endothelin-Converting Enzyme-Like 1 (ECEL1) Gene in an Emirati Child.

OBJECTIVE: The aim of this work was to report a case of an Emirati child who presented with developmental delay and multiple congenital abnormalities that are consistent with distal arthrogryposis type 5D. CLINICAL PRESENTATION AND INTERVENTION: The clinical presentation comprised contractures of the shoulders, elbows, and knees in addition to camptodactyly and neck pterygium. The facial dysmorphic features noted include ptosis and microretrognathia. Importantly, left orchidopexy was also observed and corrected surgically. Whole exome sequencing revealed that the patient is homozygous for the novel c.1184+1G>T variant in endothelin-converting enzyme-like 1 (ECEL1). CONCLUSION: This is a case of a novel homozygous splice site mutation in the ECEL1 gene in a child with a phenotype consistent with distal arthrogryposis type 5D. The child was born to consanguineous Emirati parents heterozygous for the novel ECEL1 mutation.

Microcephalic primordial dwarfism in an Emirati patient with PNKP mutation.

Microcephaly is a rare neurological condition, both in isolation and when it occurs as part of a syndrome. One of the syndromic forms of microcephaly is microcephaly, seizures and developmental delay (MCSZ) (OMIM #613402), a rare autosomal recessive neurodevelopmental disorder with a range of phenotypic severity, and known to be caused by mutations in the polynucleotide kinase 3' phosphatase (PNKP) gene. The PNK protein is a key enzyme involved in the repair of single and double stranded DNA breaks, a process which is particularly important in the nervous system. We describe an Emirati patient who presented with microcephaly, short stature, uncontrollable tonic-clonic seizures, facial dysmorphism, and developmental delay, while at the same time showing evidence of brain atrophy and agenesis of the corpus callosum. We used whole exome sequencing to identify homozygosity for a missense c.1385G > C (p.Arg462Pro) mutation in PNKP in the patient and heterozygosity for this mutation in her consanguineous parents. The Arg 462 residue forms a part of the lid subdomain helix of the P-loop Kinase domain. Although our patient's phenotype resembled that of MCSZ, the short stature and evidence of brain atrophy distinguished it from other classic cases of the condition. The report raises the question of whether to consider this case as an atypical variant of MCSZ or as a novel form of microcephalic primordial dwarfism. © 2016 Wiley Periodicals, Inc.

A novel SOX18 mutation uncovered in Jordanian patient with hypotrichosis-lymphedema-telangiectasia syndrome by Whole Exome Sequencing.

The SOX18 gene encodes a transcription factor that plays a notable role in certain developmental contexts such as lymphangiogenesis, hair follicle development and vasculogenesis. SOX18 mutations are linked to recessive and dominant hypotrichosis-lymphedema-telangiectasia syndrome (HLTS). In this study we report on a novel heterozygous mutation in SOX18 in a Jordanian patient suffering from HLTS that was revealed by Whole Exome Sequencing. In this case, a frameshift caused by 14-nucleotide duplication in SOX18 appeared de novo resulting in a premature translational stop at the N-terminal region of the central trans-activation domain. Here we present the clinical manifestations of the above mentioned molecular lesion in the light of what is known from published SOX18 mutations.

Novel ECHS1 mutation in an Emirati neonate with severe metabolic acidosis.

ECHS1 is a mitochondrial matrix enzyme that catalyzes an important step in the ß-oxidation spiral of fatty acid catabolism, and individuals with mutations in the ECHS1 gene suffer from an autosomal recessive condition typified by delayed psychomotor development, mitochondrial encephalopathy, hypotonia, and cardiomyopathy. Here we report the first Arab case of ECHS1 Deficiency. The patient was born to consanguineous parents with all growth parameters being low for gestational age, and was persistently desaturated. Cord blood gas and later blood analysis showed severe metabolic acidosis. Tandem MS revealed increased levels of valine, and Leucine/Isoleucine and decreased level of Glutamine. There was also a large patent ductus arteriosus with right to left shunt and a possible small muscular ventricular septal defect. Whole Exome Sequencing revealed a novel homozygous missense mutation in the ECHS1 gene; c.842 A > G (p.Glu281Gly). In-silico analysis suggests that the residue affected by this mutation may be involved in an important functional or structural role.

Marinesco-Sjögren Syndrome in an Emirati Child with a Novel Mutation in SIL1 Affecting the 5' Untranslated Region.

OBJECTIVE: The aim of this study was to report clinical and molecular findings in an Emirati child with Marinesco-Sjögren syndrome born to consanguineous parents. CLINICAL PRESENTATION AND INTERVENTION: The child presented with developmental delay, ataxia, bilateral cataracts, and dysmorphic craniofacial features, along with cerebellar atrophy. Sequencing of the SIL1 gene revealed a novel homozygous large indel mutation that was predicted to abrogate part of the 5' untranslated region (UTR) and the first 30 amino acids of the protein. CONCLUSION: This was a case of mutation in SIL1 that affected the 5' UTR, translation initiation site and the endoplasmic reticulum-targeting signal sequence. Further studies will be needed on the functional delineation of the mutation.

A Rare Genetic Intersection: Down Syndrome With Coexisting Spinal Muscular Atrophy.

Down syndrome (DS), characterized by trisomy of chromosome 21, and spinal muscular atrophy (SMA), an autosomal recessive neuromuscular disorder, are individually recognized distinct entities. Their co-occurrence in clinical practice is rare and has not been extensively reported. We present a case of a three-month-old, female child who presented with respiratory failure necessitating intubation. Due to typical facial features and congenital heart disease, DS was confirmed with chromosomal analysis. However, subsequent recurrent chest and bloodstream infections, failure to extubate, and laboratory abnormalities raised the suspicion of accompanying immune disorder with DS. To investigate this, whole exome sequencing analysis was sent, and it revealed a homozygous pathogenic mutation in the SMA type 1 gene in the patient. This rare intersection of two unique genetic conditions presents diagnostic challenges due to overlapping clinical features like hypotonia and delay in motor skills, which can be progressive in both situations. Additionally, the clinical trajectory, therapeutic interventions, and outcomes are variable for both conditions and a lack of guidelines for the management of two concurrent genetic conditions, such as in our patient, can pose a challenge for clinicians. Hence, this case report underscores the importance of comprehensive clinical and diagnostic evaluation in individuals with syndromic features and the need for heightened vigilance for concurrent rare genetic conditions that add to the complexity of the disease and may impact clinical outcomes, management, and counseling for the family.

Juvenile Ossifying Fibroma of the Nasal Bones: A Rare Cause of Chronic Epistaxis.

Juvenile ossifying fibroma (JOF) is a rare type of tumor originating from the bones of the face or cranium. It usually arises in the maxilla and rarely in the mandible. The complications related to the tumor are because of local expansion and resultant effect on the nearby organs. We present the case of an eight-year-old girl with a history of headache and chronic epistaxis for the past six months who presented acutely to the hospital due to swelling, redness, and pain in both eyes, with continuous epistaxis. After investigations, she was found to have a nasal tumor that was confirmed to be JOF of the nasal bone on histopathology. Surgical management was done and the tumor was resected.

A Rare Cause of Infantile-Onset Cardiomyopathy With Ocular Manifestations: Alström Syndrome.

We report a case of a five-month-old girl, who presented to our hospital with increased work of breathing, sweating since birth, and abnormal eye movements. On further evaluation, she was found to have restrictive cardiomyopathy, nystagmus, and hypotonia. Genetic workup showed a pathogenic variant in the ALSM1 gene, which confirmed the diagnosis of Alström syndrome. Alström syndrome is a rare condition that is characterized by a wide variety of multisystem manifestations, including visual disturbances, hearing impairment, and cardiomyopathy. This case report highlights Alström syndrome as one of the rare causes of early-onset infantile cardiomyopathy with nystagmus.

Expanded PCH1D phenotype linked to EXOSC9 mutation.

Pontocerebellar Hypoplasia type 1 is a rare heterogeneous neurodegenerative disorder with multiple subtypes linked to dysfunction of the exosome complex. Patients with mutations in exosome subunits exhibit a generally lethal phenotype characterized by cerebellar and pontine hypoplasia in association with spinal motor neuropathy and multiple systemic and neurologic features. Recently, two variants in the novel PCH1 associated protein EXOSC9 p.(Leu14Pro) and p.(Arg161*) have been identified in 4 unrelated patients exhibiting a severe phenotype involving cerebellar hypoplasia, axonal motor neuropathy, hypotonia, feeding difficulties, and respiratory insufficiency (PCH1D). We report clinical and molecular characterization of 2 unrelated patients exhibiting a relatively milder phenotype involving hypotonia, brachycephaly, cerebellar atrophy, psychomotor delay, as well as lactic acidosis and aberrant CNS myelination, resulting from the recurring homozygous missense mutation NM_001034194.1: c.41T>C; p.(Leu14Pro) in the EXOSC9 gene. We review the clinical picture of the EXOSC9-related PCH disorder.

Body image disturbance and surgical decision making in egyptian post menopausal breast cancer patients.

BACKGROUND: In most developing countries, as in Egypt; postmenopausal breast cancer cases are offered a radical form of surgery relying on their unawareness of the subsequent body image disturbance. This study aimed at evaluating the effect of breast cancer surgical choice; Breast Conservative Therapy (BCT) versus Modified Radical Mastectomy (MRM); on body image perception among Egyptian postmenopausal cases. METHODS: One hundred postmenopausal women with breast cancer were divided into 2 groups, one group underwent BCT and the other underwent MRM. Pre- and post-operative assessments of body image distress were done using four scales; Breast Impact of Treatment Scale (BITS), Impact of Event Scale (IES), Situational Discomfort Scale (SDS), and Body Satisfaction Scale (BSS). RESULTS: Preoperative assessment showed no statistical significant difference regarding cognitive, affective, behavioral and evaluative components of body image between both studied groups. While in postoperative assessment, women in MRM group showed higher levels of body image distress among cognitive, affective and behavioral aspects. CONCLUSION: Body image is an important factor for postmenopausal women with breast cancer in developing countries where that concept is widely ignored. We should not deprive those cases from their right of less mutilating option of treatment as BCT.

Identification of a Novel Homozygous INSR Variant in a Patient with Rabson-Mendenhall Syndrome from the United Arab Emirates.

BACKGROUND/AIMS: This study aimed to identify, clinically and molecularly, the causality of Rabson-Mendenhall syndrome in an Emirati family. It is one of the monogenic syndromes of abnormal glucose homeostasis, which result from insulin receptor defects. METHODS: A novel nonsynonymous variant in the INSR gene was uncovered by whole exome sequencing and confirmed using Sanger sequencing in the patient and his parents. Various in silico tools were utilized to analyze the functional consequences of the variant. RESULTS: Results revealed a previously unreported INSR variant in the family: c.421C>T (p.Arg141Trp). Homozygosity for the variant was found in the patient, while both parents were heterozygous. CONCLUSION: The nonsynonymous protein change hit a highly conserved arginine residue in the insulin-binding α-subunit of the receptor and was deemed 'functionally damaging' by a myriad of bioinformatics tools. This report is a step forward along the way of achieving a better molecular and clinical characterization of Rabson-Mendenhall syndrome.

Summary of mutations underlying autosomal recessive congenital ichthyoses (ARCI) in Arabs with four novel mutations in ARCI-related genes from the United Arab Emirates.

BACKGROUND: Clinical and molecular heterogeneity is a prominent characteristic of congenital ichthyoses, with the involvement of numerous causative loci. Mutations in these loci feature in autosomal recessive congenital ichthyoses (ARCIs) quite variably, with certain genes/mutations being more frequently uncovered in particular populations. METHODS: In this study, we used whole exome sequencing as well as direct Sanger sequencing to uncover four novel mutations in ARCI-related genes, which were found in families from the United Arab Emirates. In silico tools such as CADD and SIFT Indel were used to predict the functional consequences of these mutations. RESULTS: The here-presented mutations occurred in three genes (ALOX12B, TGM1, ABCA12), and these are a mixture of missense and indel variants with damaging functional consequences on their encoded proteins. CONCLUSIONS: This study presents an overview of the mutations that were found in ARCI-related genes in Arabs and discusses molecular and clinical details pertaining to the above-mentioned Emirati cases and their novel mutations with special emphasis on the resulting protein changes.

A novel nonsense GPSM2 mutation in a Yemeni family underlying Chudley-McCullough syndrome.

Mutations in the G Protein Signaling Modulator 2 (GPSM2) cause the autosomal recessive disorder Chudley-McCullough syndrome (CMS), which is characterized by profound congenital sensorineural hearing loss with various abnormalities in the brain. This phenotypic combination is attributed to the role played by GPSM2 in the establishment of planar polarity and spindle orientation during asymmetric cell divisions. Here we present two brothers from a Yemeni family who were diagnosed clinically with CMS then tested for GPSM2 mutations using Sanger sequencing. Consequent to sequencing, in silico tools (such as CADD) were utilized to assess functional consequences. Molecular analysis revealed a previously unreported homozygous mutation in GPSM2 in both brothers (c.1055C > A) leading to a truncating protein change; (p.Ser352*). This mutation is predicted to abolish all four GoLoco domains in GPSM2 and this explains the bioinformatic prediction for this mutation to be functionally damaging. Full clinical and molecular accounts of the novel mutation are provided in this paper.

Novel splice-site mutation in WDR62 revealed by whole-exome sequencing in a Sudanese family with primary microcephaly.

The WDR62 gene encodes a scaffold protein of the c-Jun N-terminal kinase (JNK) pathway. It plays a critical role in laying out various cellular layers in the cerebral cortex during embryogenesis, and hence the dramatic clinical features resulting from WDR62 mutations. These mutations are associated with autosomal recessive primary microcephaly 2, with or without cortical malformations (MCPH2). Using whole exome sequencing we uncovered a novel WDR62 variant; c.390G > A, from two Sudanese siblings whose parents are first cousins. The patients suffered MCPH2 with incomplete lissencephaly and developmental delay. The mutation affects the last nucleotide of exon4, and probably leads to aberrant splicing, which may result in a truncated protein lacking all functional domains.