CECS aka, Spike’s Disease, appears to be Paroxysmal Gluten-Sensitive Dyskinesia (PGSD) in many dogs.  Symptoms include a seizure like disorder where the dog remains fully conscious during episodes.  But signs can vary.  Age of onset is widely variable but often occurs in young adulthood.  The definitive diagnosis is to test for gluten and gliadin antibodies prior to being put on a Gluten Free diet.  At this time these tests are not available in the US.  Dogs that respond to a strict Gluten free diet are presumed to have PGSD.  No genetic markers have been associated with this disorder at this time (2022).