A novel missense mutation in causes aberrant splicing and leads to multiple mitochondrial dysfunctions syndrome 4.

Background: Iron-sulfur cluster assembly 2 (ISCA2) deficiency is linked to an autosomal recessive disorder known as multiple mitochondrial dysfunctions syndrome 4 (MMDS4). This disorder is characterized by leukodystrophy and neuroregression. Currently, most of the reported patients are from Saudi Arabia.

Dystrophin Protein Quantification as a Duchenne Muscular Dystrophy Diagnostic Biomarker in Dried Blood Spots Using Multiple Reaction Monitoring Tandem Mass Spectrometry: A Preliminary Study.

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder characterized by progressive muscle loss, leading to difficulties in movement. Mutations in the DMD gene that code for the protein dystrophin are responsible for the development of DMD disorder, where the synthesis of this protein is completely halted. Therefore, circulating dystrophin protein could be a promising biomarker of DMD disease.

Phenotypic Variability of Variants Causing Congenital Myopathy: Report of Two Unrelated Patients from a Highly Consanguineous Population.

Congenital myopathies are rare neuromuscular hereditary disorders that manifest at birth or during infancy and usually appear with muscle weakness and hypotonia. One of such disorders, early-onset myopathy, areflexia, respiratory distress, and dysphagia (EMARDD, OMIM: 614399, MIM: 612453), is a rare autosomal recessive disorder caused by biallelic mutations (at homozygous or compound heterozygous status) in (multiple epidermal growth factor-like domains protein family). Here, we report two unrelated patients, who were born to consanguineous parents, having two novel deleterious variants.

Bi-allelic variants in HOPS complex subunit VPS41 cause cerebellar ataxia and abnormal membrane trafficking.

Membrane trafficking is a complex, essential process in eukaryotic cells responsible for protein transport and processing. Deficiencies in vacuolar protein sorting (VPS) proteins, key regulators of trafficking, cause abnormal intracellular segregation of macromolecules and organelles and are linked to human disease. VPS proteins function as part of complexes such as the homotypic fusion and vacuole protein sorting (HOPS) tethering complex, composed of VPS11, VPS16, VPS18, VPS33A, VPS39 and VPS41.

Beyond a routine blood gas, an easily picked but missed diagnosis of chronic Encephalopathy.

Recessive congenital methemoglobinemia (RCM) is a rare neurological disorder caused by a deficiency in NADH-CYB5R. RCM has two main types I&II, with cyanosis being the hallmark feature in both. Type-I is a mild form, with cyanosis being the only feature.

Consensus Statement on the Management of Duchenne Muscular Dystrophy in Saudi Arabia During the Coronavirus Disease 2019 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has caused overwhelming challenges in healthcare worldwide. During such an outbreak, some needs of high-risk groups who require regular follow-ups and long-term management are not met. The vulnerable populations include patients with Duchenne muscular dystrophy (DMD).

Pyrostigmine therapy in a patient with VAMP1-related congenital myasthenic syndrome.

Congenital myasthenic syndrome comprises several genetic disorders that impair neuromuscular junction transmission. Causative mutations occur in at least 30 genes, approximately 6-8% of which are presynaptic. One such gene, VAMP1, encodes vesicle-associated membrane protein-1, which is crucial in the formation and fusion of synaptic vesicles with the presynaptic membrane at the neuromuscular junction.

The natural history of infantile neuroaxonal dystrophy.

Background: Infantile neuroaxonal dystrophy (INAD) is a rapidly progressive neurodegenerative disorder of early onset causing premature death. It results from biallelic pathogenic variants in PLA2G6, which encodes a calcium-independent phospholipase A2.

Objective: We aim to outline the natural history of INAD and provide a comprehensive description of its clinical, radiological, laboratory, and molecular findings.

Rett Syndrome, a Neurodevelopmental Disorder, Whole-Transcriptome, and Mitochondrial Genome Multiomics Analyses Identify Novel Variations and Disease Pathways.

Rett syndrome (RTT) is a severe neurodevelopmental disorder reported worldwide in diverse populations. RTT is diagnosed primarily in females, with clinical findings manifesting early in life. Despite the variable rates across populations, RTT has an estimated prevalence of ∼1 in 10,000 live female births.

The morbid genome of ciliopathies: an update.

Purpose: Ciliopathies are highly heterogeneous clinical disorders of the primary cilium. We aim to characterize a large cohort of ciliopathies phenotypically and molecularly.

Methods: Detailed phenotypic and genomic analysis of patients with ciliopathies, and functional characterization of novel candidate genes.

Tuberous Sclerosis Complex: Clinical Spectrum and Epilepsy: A Retrospective Chart Review Study.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic neurocutaneous disorder, with heterogeneous manifestations. We aimed to review the clinical presentation of TSC and its association with epilepsy among Saudi population. This was a retrospective chart review study of 88 patients diagnosed with TSC with or without epilepsy.

Carbon nanofiber-based multiplexed immunosensor for the detection of survival motor neuron 1, cystic fibrosis transmembrane conductance regulator and Duchenne Muscular Dystrophy proteins.

Simultaneous and point-of-care detection of multiple protein biomarkers has significant impact on patient care. Spinal Muscular Atrophy (SMA), Cystic Fibrosis (CF) and Duchenne Muscular Dystrophy (DMD) are well known progressive hereditary disorders associated with increased morbidity as well as mortality. Therefore, rapid detection of biomarkers specific for these three disorders in newborns offers new opportunities for early diagnosis, delaying symptoms and effective treatment.

A Novel Homozygous Mutation in SPTBN2 Leads to Spinocerebellar Ataxia in a Consanguineous Family: Report of a New Infantile-Onset Case and Brief Review of the Literature.

The objective of this study was the identification of likely genes and mutations associated with an autosomal recessive (AR) rare spinocerebellar ataxia (SCA) phenotype in two patients with infantile onset, from a consanguineous family. Using genome-wide SNP screening, autozygosity mapping, targeted Sanger sequencing and nextgen sequencing, family segregation analysis, and comprehensive neuropanel, we discovered a novel mutation in SPTBN2. Next, we utilized multiple sequence alignment of amino acids from various species as well as crystal structures provided by protein data bank (PDB# 1WYQ and 1WJM) to model the mutation site and its effect on β-III-spectrin.

COLQ-mutant Congenital Myasthenic Syndrome with Microcephaly: A Unique Case with Literature Review.

Congenital Myasthenic Syndrome (CMS) is a group of inherited neuromuscular junction disorders caused by defects in several genes. Clinical features include delayed motor milestones, recurrent respiratory illnesses and variable fatigable weakness. The central nervous system involvement is typically not part of the CMS.

The landscape of genetic diseases in Saudi Arabia based on the first 1000 diagnostic panels and exomes.

In this study, we report the experience of the only reference clinical next-generation sequencing lab in Saudi Arabia with the first 1000 families who span a wide-range of suspected Mendelian phenotypes. A total of 1019 tests were performed in the period of March 2016-December 2016 comprising 972 solo (index only), 14 duo (parents or affected siblings only), and 33 trio (index and parents). Multigene panels accounted for 672 tests, while whole exome sequencing (WES) represented the remaining 347 tests.

Novel FGD1 mutation underlying Aarskog-Scott syndrome with myopathy and distal arthropathy.

In this report, we describe a kindred consisting of five affected males presenting with many of the well-recognized features of Aarskog-Scott syndrome. The diagnosis, which was confirmed by the identification of a novel nonsense mutation of FGD1, was associated with the presence of a symmetric distal arthropathy with electromyographic signs of myopathy. These features should be considered in the evaluation of future patients.

Variant late infantile neuronal ceroid lipofuscinosis (CLN6 gene) in Saudi Arabia.

Variant late infantile neuronal ceroid lipofuscinosis is one of the multiethnically prevalent types of neuronal ceroid lipofuscinoses. Reported here are three families representing the first cases from Saudi Arabia, one of them having a novel mutation in the CLN6 gene. The CLN6-related literature is reviewed.

Vanishing white matter in Saudi Arabia.

Vanishing white matter disease (VWMD) is an under-diagnosed condition that affects the brains white matter at all ages, especially in the pediatric age group. It belongs to a clinically and genetically heterogeneous group of disorders, collectively known as eukaryotic initiation factor 2B-related disorders. The disorder has been described in different ethnic groups.