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. We evaluated the clinical, biomarker and genetic spectrum of 15 Egyptian children from 14 unrelated families with biallelic pathogenic variants in ASAH1 (12 Farber and 3 SMA-PME). Recruited children were nine females/six males ranging in age at diagnosis from 13 to 118 months. We detected ASAH1 pathogenic variants in all 30 alleles including three novel variants (c.1126A>G (p.Thr376Ala), c.1205G>A (p.Arg402Gln), exon-5-deletion). Both total C26-Ceramide and its trans- isomer showed 100% sensitivity for the detection of ASAH1-related disorders in tested patients. A 10-year-old girl with the novel variant c.1205G>A (p.Arg402Gln) presented with a new peculiar phenotype of PME without muscle atrophy. We expanded the phenotypic spectrum of ASAH1-related disorders and validated the biomarker C26-Ceramide for supporting diagnosis in symptomatic patients.

Genetic and Molecular Evaluation: Reporting Three Novel Mutations and Creating Awareness of Pycnodysostosis Disease.

Pycnodysostosis is a rare autosomal recessive disorder with characteristic diagnostic manifestations. This study aims to phenotype and provide molecular characterization of Egyptian patients, with emphasis on identifying unusual phenotypes and raising awareness about pycnodysostosis with different presentations to avoid a mis- or under-diagnosis and consequent mismanagement. We report on 22 Egyptian pycnodysostosis patients, including 9 new participants, all descending from consanguineous families and their ages ranging from 6 to 15 years. In addition, prenatal diagnosis was performed in one family with affected siblings. They all presented with short stature, except for one patient who presented with pancytopenia as her primary complaint. Moreover, 41.2% of patients had sleep apnea, 14% presented with craniosynostosis, and 44.4% had failure of tooth development. Molecular analysis via direct exome sequencing of the cathepsin K gene revealed three novel mutations ((NM_000396.3) c.761_763delCCT, c.864_865delAA, and c.509G>T) as well as two previously reported mutations among nine new cases. The following is our conclusion: This study expands the molecular spectrum of pycnodysostosis by identifying three novel mutations and adds to the clinical and orodental aspects of the disease. The link between the CTSK gene mutations and the failure of tooth development has not been established, and further studies could help to improve our understanding of the molecular pathology.

Prevalence of Congenital Ocular Anomalies among Children with Genetic Disorders: An Egyptian Study.

PURPOSE: To assess the pattern and frequency of occurrence of ocular anomalies among other genetic disorders in Egypt. METHODS: This is a cross-sectional study of 2500 cases presenting with genetic disorders. Cases were recruited from the clinical genetics department of the National Research Centre (NRC) over a four-year period between January 2011 and December 2014. Ophthalmological examination of the cases was performed in the pediatric ophthalmology department of Cairo University Hospitals. RESULTS: Out of 2500 cases with congenital disorders, 2.4% suffered one or more ocular anomalies with a male to female ratio of 1.7:1. Consanguinity was reported in 76.7% and family history was positive in 35% of ocular cases. The most common ocular anomalies were congenital cataract, retinal dystrophies, glaucoma, and retinoblastoma in order of frequency. Chromosomal aberrations were detected in two retinoblastoma cases and in one case of charge association with cataract and iris coloboma. A truncating mutation in exon 8 of OCRL1 was reported in a case of Lowe syndrome with cataract. A total of 51.7% of ocular cases were non-isolated (associated with other genetic disorders). CONCLUSION: In Egypt, ocular genetic disorders are not uncommon among other genetic disorders. Consanguinity is high, suggesting high incidence of autosomal recessive inheritance of genetic disorders with an ocular component. Proper systemic assessment of all cases with ocular anomalies is a necessity due to the high percentage of non-isolated ocular anomalies. Genetic counseling of parents would help in reducing recurrence rates through prenatal diagnosis whenever possible.

Registry of ocular anomalies among patients with genetic disorders attending the clinical genetics department at the National Research Center in Egypt.

BACKGROUND: The congenital abnormalities of eyes are a major cause of visual impairment throughout the world. Prevention of visual impairment due to congenital and infantile abnormalities of eyes is very important. The aim of this study is to evaluate the frequency and types of congenital ocular anomalies among patients with genetic disorders. PATIENTS AND METHODS: This is a retrospective study that was conducted in the National Research Center, Egypt at the Clinical Genetics Department over a 4-year period. Out of 2500 patients attending the outpatient clinics, a total of 61 patients with congenital ocular malformations (2.44%) were included in this study. They underwent clinical and genetic assessments. RESULTS AND CONCLUSIONS: Isolated ocular malformations were found in 70.5% while complex ocular anomalies were found in 29.5%. A total of 37.7% of the patients had a known recognizable syndrome, 24.6% of the patients were classified as having metabolic disorders and 37.7% of the patients were classified as having isolated disorders. Chromosomal abnormalities were found in 4.9% of the patients. Congenital cataract was the most frequent feature in syndromic, metabolic, and isolated disorders. Our study elucidates the significance of the early detection of ocular anomalies for appropriate diagnosis of genetic disorders.