Cost-effectiveness of genetic testing in patients with epilepsy: which test is the right test?

Which test is the right test? In clinical practice, determining an appropriate genetic testing strategy in the evaluation of a patient with unexplained epilepsy is often inconsistent and left to the treating provider, given the lack of evidence-based guidelines. Oftentimes external factors, such as insurance hurdles, dictate the genetic testing that can be ordered. A recent meta-analysis in Neurology attempts to answer the question about which genetic test is most cost-effective in patients with epilepsy, which may aid in the decision making when considering a genetic evaluation of a person with epilepsy. Continue reading

Three reasons why exomes are like MRIs – and three reasons why they are not

Exome rounds. How will next-generation sequencing technologies impact on patient care in the future? What role will genetic analyses play in routine health care? Sometimes, the possible role of genetic information is compared to the role of MRI imaging, including the general expertise that is required of clinicians who apply these technologies but are not necessarily dedicated experts in the field. Here are three interesting parallels between exomes and MRI – and three examples how the impact of these technologies differs drastically. Continue reading

Less is more – gene identification in epileptic encephalopathies through targeted resequencing

Exome no more. Over the last 15 months, we have repeatedly discussed how exome sequencing or genome sequencing is applied to neurodevelopmental disorders in order to discover new candidate genes and to assess the role of known candidate genes. We have also wondered sometimes whether exome sequencing is the most straightforward approach. Now – outpacing the two large international consortia using exome sequencing in epileptic encephalopathies – a recent study in Nature Genetics uses a different approach to uncover the genetic basis in 10% of patients with epileptic encephalopathies.  Targeted resequencing or gene panel analysis is a hybrid technology between candidate gene sequencing and next generation sequencing and focuses only on a subset of candidate genes. While their study provides a comprehensive overview over the genetics of rare epilepsy syndromes, it raises the question whether the era of large-scale exome sequencing is coming to a natural end. Continue reading

Missed SCN1A mutations in Dravet Syndrome – a matter of degrees

Back from AES. I have just come back from the 66th Annual Meeting of the American Epilepsy Society and I would like to share some of the most recent findings that were presented at this meeting. Since we felt that our presentation on the “re-discovery” of SCN1A mutations in SCN1A-negative patients with Dravet Syndrome received quite some attention, I thought that I would share this part of our presentation as a brief screencast. In particular, I would like to thank Anna-Kaisa Anttonen and Anna-Elina Lehesjoki for providing us with the trace files. And of course thanks to everybody in RES who was involved in this.