The DNM1 gene encodes dynamin-1, a protein playing an important role in signal transduction from one neuron to another. This neuronal communication uses release of neurotransmitters stored in vesicles beneath the neuronal membrane. Dynamin-1 induces membrane constriction subsequently resulting in vesicle fission from the membrane.

Missense variants in DNM1 were found to be associated with developmental and epileptic encephalopathies, but only mono-allelic variants were reported. We detected bi-allelic loss-of-function variants in DNM1 in two unrelated patients with a severe neurodevelopmental disorder.

This is a further example of a gene in which the type of mutation and its functional effect determine the inheritance pattern and phenotypic outcome of the disease. (By Dr. Knut Brockmann, https://jmg.bmj.com/content/early/2021/06/25/jmedgenet-2021-107769 )