GRIN2A. Mutations in several genes coding for NMDA receptor subunits have recently been found in various neurodevelopmental disorders. Amongst the different genes, GRIN2A is one of the most prominent ones and mutations in this gene are found in patients with epilepsy-aphasia syndromes. So far, we have mainly looked at GRIN2A from the epilepsy side. In a recent publication in Neurology, Turner and collaborators now examine the speech phenotype in GRIN2A families. They examine two families where speech issues are a prominent phenotypic feature. It turns out that GRIN2A mutations may predispose to a distinct speech phenotype. Continue reading
Tag Archives: SRPX2
ESES and the postsynapse – CNKSR2 in genetic epilepsies
Structure. Despite tremendous advances in understanding its genetic underpinnings in the last few years, electrical status epilepticus during slow-wave sleep (ESES) is a poorly understood neurodevelopmental disorder and to a certain extent the prototype of an epileptic encephalopathy. Slow-wave sleep in affected children is entirely replaced by epileptiform activity, leading to significant neurocognitive impairment with an emphasis on speech impairment. In a recent publication in Annals of Neurology, alterations in CNKSR2 are identified in families with a more severe course of ESES, highlighting the postsynapse as a possible player in ESES pathogenesis. Continue reading
Copy numbers, seizures and speech
Why does this child with speech delay get an EEG? My first encounter with Landau-Kleffner-Syndrome and continuous spikes and waves during slow sleep (CSWS) was in medical school when my pediatric neurology attending faced me with this very question. I looked at him and basically had no idea. This is when I learned about the spectrum of rolandic epilepsies and how epilepsy interacts with speech. This concept is best explained by going back to the most common epilepsy in children, Benign Rolandic Epilepsy (BRE). And the genetics of BRE and the rolandic spectrum has been anything else but straightforward. Continue reading
What’s the Frequency, Kenneth? The story of LGI1
Can’t you hear the radio? “S.W. was spending an afternoon at this girlfriend’s house when he suddenly heard a radio sound in his right ear. He asked his girlfriend whether she was aware of this sound as well, but he could not understand her answer. S.W. then lost consciousness and convulsed. He presented with a second seizure several months later. S.W. was started on carbamazepine and remained seizure-free. Interestingly, his mother had seizures starting at the same age. Furthermore, his sister had her first seizure at the age of 8 years and frequently reported auras where she would see colourful pictures and hear noises like a familiar song. These episodes sometimes occurred seconds before she had a generalised tonic-clonic seizure.”
LG-what? This impressive case report taken from Steven Waxman’s Molecular Neurology illustrates a family with lateral temporal lobe epilepsy (LTLE), a rare form of seizure disorder in which auditory features often precede a generalized tonic-clonic seizure. Auditory or acoustic features including radio sounds, machine noises or more complex acoustic phenomena arise from the lateral temporal lobe, a part of the brain important for auditory processing. During a discussion with one of our students last week, I realised that even though we frequently write about microdeletions and novel gene findings on the EuroEPINOMICS blog, some of the classics of epilepsy genetics may sometimes be revisited as well. LTLE is the premier example that genetic epilepsies are not neccesarily due to ion channels. Continue reading
