Clinical and Genetic Spectrum of Patients With Mitochondrial Disease in a Pediatric Egyptian Cohort: Novel Variants and Phenotypic Expansion.

Mitochondrial disorders exhibit clinical and genetic diversity. Nearly 400 distinct genes, located in both the mitochondrial and nuclear genomes, harbor pathogenic variants that can produce a broad spectrum of mitochondrial diseases. This work aims to explore the genetic etiology of a cohort of Egyptian pediatric patients who were clinically suspected of having a mitochondrial disorder.

Importance of the biochemical investigations for the functional characterization of a NPC1 variant identified by exome sequencing.

Niemann-Pick disease type C (NPC) is one of the lysosomal storage disorders. It is caused by biallelic pathogenic variants in NPC1 or NPC2, which results in a defective cholesterol trafficking inside the late endosome and lysosome. There is a high clinical variability in the age of presentation and the phenotype of this disorder making the diagnosis challenging.

Neurodevelopmental disorders associated variants in disrupt the activity of the ADAT2/ADAT3 tRNA deaminase complex and impair neuronal migration.

The ADAT2/ADAT3 complex catalyzes the adenosine to inosine modification at the wobble position of eukaryotic tRNAs. Mutations in , the catalytically inactive subunit of the ADAT2/ADAT3 complex, have been identified in patients presenting with severe neurodevelopmental disorders (NDDs). Yet, the physiological function of ADAT2/ADAT3 complex during brain development remains totally unknown.

Clinical and biochemical phenotypes, genotypes, and long-term outcomes of individuals with galactosemia type I from a single metabolic genetics center in Alberta.

Background: Galactosemia type I is an autosomal recessive disorder of galactose metabolism due to galactose-1-phosphate uridyltransferase deficiency, encoded by . To investigate the phenotypes, genotypes and long-term outcomes of galactosemia, we performed a retrospective cohort study in our center.

Methods: All individuals with galactosemia type I were included.

Clinical, biochemical, and molecular characterization of mucopolysaccharidosis type III in 34 Egyptian patients.

Mucopolysaccharidosis type III (MPS III) is a rare autosomal recessive lysosomal storage disorder characterized by progressive neurocognitive deterioration. There are four MPS III subtypes (A, B, C, and D) that are clinically indistinguishable with variable rates of progression. A retrospective analysis was carried out on 34 patients with MPS III types at Cairo University Children's Hospital.

Clinical and biochemical spectrum of metabolic cardiomyopathy in Egyptian children.

Background: Inborn errors of metabolism (IEMs) commonly present with pediatric cardiomyopathy. Identification of the underlying cause is necessary as it may lead to improved outcomes.

Objectives: We aimed to investigate the diagnostic rate, the clinical, and biochemical spectra of IEMs among Egyptian pediatric patients presenting with cardiomyopathy, and their outcome measures.

Clinical and genetic spectrum of mitochondrial DNA depletion syndromes: A report of 6 cases with 4 novel variants.

Unlabelled: Mitochondrial DNA (mtDNA) depletion syndromes (MDS) are a heterogeneous group of rare autosomal recessive genetic disorders characterized by a decrease in the number of mtDNA copies inside the organ involved. There are three distinct forms of MDS including the hepatocerebral, the myopathic and the encephalomyopathic forms. The diversity in the clinical and genetic spectrum of these disorders makes the diagnosis challenging.

ASAH1-related disorders: Description of 15 novel pediatric patients and expansion of the clinical phenotype.

Acid ceramidase deficiency is an orphan lysosomal disorder caused by ASAH1 pathogenic variants and presenting with either Farber disease or spinal muscle atrophy with progressive myoclonic epilepsy (SMA-PME). Phenotypic and genotypic features are rarely explored beyond the scope of case reports. Furthermore, the new biomarker C26-Ceramide requires validation in a clinical setting.