Filling in. As Dennis is current fully engaged in the Helsinki meeting, I am filling in for him to present the most relevant publications in the field published in the last two weeks. This week’s publications were about functional studies, phenotype delineations, and novel gene findings. Continue reading
Tag Archives: Dravet Syndrome
The return of the h-current: HCN1 mutations in atypical Dravet Syndrome
Hyperpolarization. More than a quarter of a century ago, physiologists identified an electrical current in neurons and cardiac myocytes that behaved so strangely that it was called the “queer” or “funny” current: it paradoxically caused depolarization upon hyperpolarization. This current was finally named h-current and is mediated by HCN channels. The h-current has been associated with epilepsy through functional studies, but a genetic link has been elusive so far. In a recent publication in Nature Genetics, de novo mutations in HCN1 are identified in patients with early-onset epileptic encephalopathies resembling Dravet Syndrome. Continue reading
GABRA1 and STXBP1 as novel genes for Dravet Syndrome
Beyond SCN1A. Dravet Syndrome is a severe fever-associated epileptic encephalopathy. While the large majority of patients with Dravet Syndrome carry mutations in the SCN1A gene, the genetic basis is unknown in up to 20% of patients. Some female patients with Dravet-like epilepsies have mutations in PCDH19, but other than this, no additional major gene for typical Dravet Syndrome is known. In a recent paper in Neurology, de novo mutations in GABRA1 and STXBP1 are identified as novel causes for Dravet Syndrome. In addition, several SCN1A-negative patients were shown to have mutations in SCN1A that were initially missed. Continue reading
Papers of the week – GABRA1 and STXBP1 in Dravet, gene therapy & synonymous mutations in cancers
FASTA, FASTQ, SAM, BAM, BWA, GC, GATK, IGV. Phew. Day 2 at the EuroEPINOMICS bioinformatics workshop in Leuven. Usually my work starts after the initial NGS raw data quality control and mapping procedures. Today’s topics are supposed to improve my understanding of sequencing analysis and NGS data interpretation. While we are still struggling, other scientists have done their home work already. Here are some of the remarkable publications from this week.
Papers of the week – 15q11 duplications, Olig1 & Automated decision-making
A productive week in epilepsy genetics. Scientists and editors were certainly busy this week reporting novel variants and deletions as well the experimental and statistical advances for their interpretation.
A de novo GRIN2A missense mutation in early-onset epileptic encephalopathy. We and others have associated variants affecting the GRIN2A gene with a range of childhood focal epilepsy syndromes. Continue reading
Papers of the week – next-level mutation classifiers and 3’UTR variants in Dravet Syndrome
The future is now. This week’s publications of the week are about the next generation of in silico mutation interpretation, the power of a full genetic screen in neurodegenerative motor neuron diseases and a possible 3’UTR mutation in Dravet Syndrome. Continue reading
Papers of the week – WES Meta analysis, Dravet mice & large sequencing studies
Time flies – already thursday night again. Here are updates on study designs to identify rare pathogenic mutations in neurodevelopment diseases, an epilepsy animal model study as well as novel statistical frameworks for large genetic screens.
The placebo effect. In a recent paper in Science Translational Medicine the group of Kam-Hansen investigated the effect of altered placebo and drug labeling changes and its outcome in patients with episodic migraine. Their results suggest that the placebo accounted for more than 50% of the drug effect.
Modifier genes in Dravet Syndrome: where to look and how to find them
Converging thoughts. During late 2013, I had several unrelated discussions about the possible role of genetic modifiers of SCN1A in Dravet Syndrome. To some extent, SCN1A is a paradox. One the one hand, the connection between Dravet Syndrome and SCN1A is one of the clearest connections between gene and disease that we see in genetic epilepsies. On the other hand, we see a remarkable phenotypic heterogeneity in families, and some presumably pathogenic SCN1A variants can also be identified in unaffected control individuals. This leaves us with the question whether there are genetic modifiers in Dravet Syndrome that might help provide some insight into additional mechanisms of disease. This post is a collection of 10 individual thoughts that emerged during the discussions last year. Continue reading
Story of a genetic shape-shifter: SCN2A in benign seizures, autism and epileptic encephalopathy
The other sodium channel gene. The week before Christmas, the Kiel group identified its first patient with SCN2A encephalopathy. At the same time, a questionably benign SNP in the same gene is haunting our Israel Epilepsy Family Project. Time to review the mysterious SCN2A gene that initially entered the scene as a candidate for a rare, benign familial epilepsy syndrome – only to return as one of the most prominent genes for autism, intellectual disability, and epileptic encephalopathies to date. Continue reading
2013 in review: top three lists and the gene finding of the year
Gene of the year. Let’s take a minute to look back at the very busy year of 2013. There were major advances in many areas of epilepsy genetics. First and foremost, massive (and I mean massive) progress has been made in the genetics of the epileptic encephalopathies, where de novo mutations have been identified as a major source of genetic morbidity. Secondly, the new technologies have made it possible to identify several novel genes for various epilepsy types. Out of these genes, we have again selected the most important finding in 2013. And the gene finding of the year is… Continue reading