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.

Expanding the phenotypic and mutational spectrum in microcephalic osteodysplastic primordial dwarfism type I.

Mutations in the RNU4ATAC gene cause microcephalic osteodysplastic primordial dwarfism type I. It encodes U4atac, a small nuclear RNA that is a component of the minor spliceosome. Six distinct mutations in 30 patients diagnosed as microcephalic osteodysplastic primordial dwarfism type I have been described. We report on three additional patients from two unrelated families presenting with a milder phenotype of microcephalic osteodysplastic primordial dwarfism type I and metopic synostosis. Patient 1 had two novel heterozygous mutations in the 3' prime stem-loop, g.66G > C and g.124G > A while Patients 2 and 3 had a homozygous mutation g.55G > A in the 5' prime stem-loop. Although they manifested the known spectrum of clinical features of microcephalic osteodysplastic primordial dwarfism type I, they lacked evidence of severe developmental delay and neurological symptoms. These findings expand the mutational and phenotypic spectrum of this syndrome.