DNM1 and when transcripts matter more than genes

What comes next. Earlier this month, Ingo made a bit of a splash at the American Epilepsy Society Annual Course, with his surprising comment that, in some contexts, “genes don’t matter.” This was in reference to transcripts and gene expression, which ultimately determine if and how variants can cause disease. In this post, I wanted to explore this idea, diving into the world of transcripts and their increasing relevance in approaching diagnosis and treatment of genetic epilepsies and neurodevelopmental disorders. And I wanted to share one of the most surprising findings in epilepsy genetics in 2022, namely, how examining transcripts rather than genes helped us understand how an intronic variant can be dominant-negative. Continue reading

Entering the phenotype era – HPO-based similarity, big data, and the genetic epilepsies

Semantic similarity. The phenotype era in the epilepsies has now officially started. While it is possible for us to generate and analyze genetic data in the epilepsies at scale, phenotyping typically remains a manual, non-scalable task. This contrast has resulted in a significant imbalance where it is often easier to obtain genomic data than clinical data. However, it is often not the lack of clinical data that causes this problem, but our ability to handle it. Clinical data is often unstructured, incomplete and multi-dimensional, resulting in difficulties when trying to meaningfully analyze this information. Today, our publication on analyzing more than 31,000 phenotypic terms in 846 patient-parent trios with developmental and epileptic encephalopathies (DEE) appeared online. We developed a range of new concepts and techniques to analyze phenotypic information at scale, identified previously unknown patterns, and were bold enough to challenge the prevailing paradigms on how statistical evidence for disease causation is generated. Continue reading

DNM1 encephalopathy – a new disease of vesicle fission

Dynamin 1. Our recognition of DNM1 encephalopathy as a novel disease started out as a digital flicker. Deep inside some of the large-scale studies in epilepsy genetics, there were a few patients with de novo mutations in the gene coding for DNM1. However, amongst all the other likely and less likely candidates, it took a while for DNM1 to emerge as a true candidate. But even then, being a disease gene born out of large-scale studies with little information on clinical presentation and disease course, we had learned little about how patients with DNM1 encephalopathy actually present and how they develop over time. In our recent publication in Neurology, we describe the spectrum of DNM1 encephalopathy, including an unusual mutational landscape and the first genetic cause in a patient with FIRES. Continue reading