Exome sequencing revealed a novel homozygous METTL23 gene mutation leading to familial mild intellectual disability with dysmorphic features.

BACKGROUND: Genetic factors represent a considerable part of the etiologies of intellectual disability; however, the identification of causal genetic anomaly has long been complicated by the great clinical and genetic heterogeneity of this type of disease. With advances in next-generation sequencing technologies and functional studies, the identification of genes involved in intellectual development has led to more accurate diagnostics and better understanding of the underlying biological pathways. CASE REPORT: We report on the case of two Moroccan siblings presenting mild intellectual disability with minimal dysmorphic features in which whole exome sequencing analysis revealed homozygous mutation in the METTL23 gene. Mutations in this gene have been reported to cause autosomal recessive mild intellectual disability but the association with dysmorphic features remains controversial. CONCLUSION: Hereby, we highlight the similarity of the dysmorphic traits and the characteristic facial features in patients with METTL23-related intellectual disability, suggesting the consideration of a distinct clinical entity associating mild intellectual deficiency with specific facial dysmorphy for an efficient diagnosis orientation and a better phenotype-genotype correlation in intellectual disability disorders.

[Mechanical ventilation during MRI in children. Anesthetic constraints]. / La ventilation mécanique en IRM chez l'enfant. Contraintes anesthésiques.

Early use of magnetic resonance imaging (MRI) excluded patients needing mechanical ventilation. However magnetic resonance imaging is an innocuous investigation and affords important elements to the diagnosis of many pathologies. Improvement of anaesthetic equipment have led to enlarge MRI applications considerably. Ventilations situated outside the MRI room required very long tubing, to 9-11 m. Although the ferromagnetic charge of presently used ventilators is greatly reduced, it is still necessary to keep them at some distance from the patient, with tubing of about 3 m, even in children. Therefore the compressible gas volumes are larger than the usual ones. For a tube length of 3 m, about 2-3 ml.kg-1 should be added to the standard tidal volume (10 ml.kg-1), so as to obtain safe normoventilation.