ABSTRACT
OBJECTIVES: Acatalasemia is a very rare disorder characterized by gangrenous oral ulcerations and is caused by biallelic variants in the CAT gene which encodes the catalase enzyme that decomposes the hydrogen peroxide molecules to remove their toxic effect. We report two siblings from a consanguineous Egyptian family presenting with joint hyperlaxity, loose dentitions with gangrenous periodontitis, and early loss of teeth. STUDY DESIGN: The patients were clinically suspected to have the periodontal type of Ehlers-Danlos syndrome and thus genetic testing of C1S and C1R causative genes was carried out first by Sanger sequencing then exome sequencing (ES) was considered. RESULTS: No pathogenic variants were detected in C1S and C1R genes then ES revealed a new homozygous missense variant in the CAT gene segregating in the family, c .635 T > G (p.Met212Arg). CONCLUSION: We describe the first Egyptian cases with acatalasemia and expand the mutational spectrum of this rare disorder. Premature loss of teeth is an emerging finding in our cases and addresses the hazardous systemic manifestations associated with the disorder. The rarity of inherited orodental diseases renders the accurate diagnosis difficult and complicates the symptoms. Therefore, the use of advanced molecular technologies is highly advisable for early diagnosis and management of patients.
Subject(s)
Catalase , Mutation, Missense , Pedigree , Periodontitis , Humans , Male , Periodontitis/genetics , Female , Catalase/genetics , Egypt , Consanguinity , Oral Ulcer/genetics , Gangrene/genetics , Exome SequencingABSTRACT
OBJECTIVES: describing the clinical features of twelve Egyptian patients with Papillon-Lefever syndrome (PLS). Five novel mutations in the cathepsin C (CTSC) gene are introduced and the phenotype of the syndrome is expanded by the identification of new clinical features. DESIGN: the clinical, oro-dental data of twelve Egyptian patients from seven unrelated families are described. Sequence analysis of the CTSC gene was performed to identify the causative mutaions. RESULTS: Typical PLS features were presented in all patints but with variable severity. One patient showed atypical dental features including dental structural defect, minimal periodontitis, severe gingivitis, and delayed closure of root apices. Another patient presented with arachnodactyly, dystrophic nails, and buphthalmos in the right eye secondary to uncontrolled congenital glaucoma. Mutational analysis of CTSC gene revealed seven distinct homozygous variants including five novel ones: c.285_286delGT (p.Leu96GlufsTer2), c .302 G>C (p.Trp101Ser), c.622_628delCACAGTC (p.H208Efs*11), c.1331delinsAAAAA (p.G444Efs*4) and c .1343 G>A (p.Cys448Tyr). The previously reported missense variant c .757 G>A (p.Ala253Thr) was found in one patient. This variant is very close to the splice region and by functional studies, we proved that it results in exon skipping and early protein truncation (p.R214Sfs*46). CONCLUSION: We report five novel CTSC variants and describe rare and unusual associated clinical and dental findings such as dental structural defects, delayed closure of root apices, and congenital glaucoma. Therefore, our results expand both the phenotypic and mutational spectrum of PLS.
Subject(s)
Glaucoma , Papillon-Lefevre Disease , Humans , Papillon-Lefevre Disease/genetics , Cathepsin C/chemistry , Cathepsin C/genetics , Egypt , Mutation, Missense , SyndromeABSTRACT
Ectodermal dysplasia (ED) is a diverse group of genetic disorders caused by congenital defects of two or more ectodermal-derived body structures, namely, hair, teeth, nails, and some glands, e.g., sweat glands. Molecular pathogenesis of ED involves mutations of genes encoding key proteins of major developmental pathways, including ectodysplasin (EDA) and wingless-type (WNT) pathways. The most common ED phenotype is hypohidrotic/anhidrotic ectodermal dysplasia (HED) featuring hypotrichosis, hypohidrosis/anhidrosis, and hypodontia. Molecular diagnosis is fundamental for disease management and emerging treatments. We used targeted next generation sequencing to study EDA, EDAR, EDARADD, and WNT10A genes in 45 Egyptian ED patients with or without hypohidrosis. We present genotype and phenotype data of 28 molecularly-characterized patients demonstrating genetic heterogeneity, variable expressivity, and intrafamilial phenotypic variability. Thirteen mutations were reported, including four novel EDA mutations, two novel EDARADD, and one novel EDAR mutations. Identified mutations congregated in exons encoding key functional domains. EDA is the most common gene contributing to 85% of the identified Egyptian ED genetic spectrum, followed by EDARADD (10%) and EDAR (5%). Our cohort represents the first and largest cohort from North Africa where more than 60% of ED patients were identified emphasizing the need for exome sequencing to explore unidentified cases.
Subject(s)
Ectodermal Dysplasia/genetics , Ectodysplasins/genetics , Edar Receptor/genetics , Edar-Associated Death Domain Protein/genetics , Mutation , Adult , Child , Child, Preschool , Ectodermal Dysplasia/etiology , Egypt , Female , Heterozygote , Humans , Infant , Male , Middle Aged , Wnt Proteins/geneticsABSTRACT
PCNT encodes a large coiled- protein localizing to pericentriolar material and is associated with microcephalic osteodysplastic primordial dwarfism type II syndrome (MOPD II). We report our experience of nine new patients from seven unrelated consanguineous Egyptian families with the distinctive clinical features of MOPD II in whom a customized NGS panel showed homozygous truncating variants of PCNT. The NGS panel results were validated thereafter using Sanger sequencing revealing three previously reported and three novel PCNT pathogenic variants. The core phenotype appeared homogeneous to what had been reported before although patients differed in the severity showing inter and intra familial variability. The orodental pattern showed atrophic alveolar ridge (five patients), rootless tooth (four patients), tooth agenesis (three patients), and malformed tooth (three patients). In addition, mesiodens was a novel finding found in one patient. The novel c.9394-1G>T variant was found in two sibs who had tooth agenesis. CNS anomalies with possible vascular sequelae were documented in two male patients (22.2%). Simplified gyral pattern with poor development of the frontal horns of lateral ventricles was seen in four patients and mild thinning of the corpus callosum in two patients. Unilateral coronal craniosynstosis was noted in one patient and thick but short corpus callosum was an unusual finding noted in another. The later has not been reported before. Our results refine the clinical, neuroradiological, and orodental features and expand the molecular spectrum of MOPD II.