title: Exome sequencing of ion channel genes reveals complex profiles confounding personal risk assessment in epilepsy.
abstract: Ion channel mutations are an important cause of rare Mendelian disorders affecting brain, heart, and other tissues. We performed parallel exome sequencing of 237 channel genes in a well-characterized human sample, comparing variant profiles of unaffected individuals to those with the most common neuronal excitability disorder, sporadic idiopathic epilepsy. Rare missense variation in known Mendelian disease genes is prevalent in both groups at similar complexity, revealing that even deleterious ion channel mutations confer uncertain risk to an individual depending on the other variants with which they are combined. Our findings indicate that variant discovery via large scale sequencing efforts is only a first step in illuminating the complex allelic architecture underlying personal disease risk. We propose that in silico modeling of channel variation in realistic cell and network models will be crucial to future strategies assessing mutation profile pathogenicity and drug response in individuals with a broad spectrum of excitability disorders.
authors.affiliation: Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Tara
authors.initials: T
authors.lastname: Klassen
authors.forename: Caleb
authors.initials: C
authors.lastname: Davis
authors.forename: Alica
authors.initials: A
authors.lastname: Goldman
authors.forename: Dan
authors.initials: D
authors.lastname: Burgess
authors.forename: Tim
authors.initials: T
authors.lastname: Chen
authors.forename: David
authors.initials: D
authors.lastname: Wheeler
authors.forename: John
authors.initials: J
authors.lastname: McPherson
authors.forename: Traci
authors.initials: T
authors.lastname: Bourquin
authors.forename: Lora
authors.initials: L
authors.lastname: Lewis
authors.forename: Donna
authors.initials: D
authors.lastname: Villasana
authors.forename: Margaret
authors.initials: M
authors.lastname: Morgan
authors.forename: Donna
authors.initials: D
authors.lastname: Muzny
authors.forename: Richard
authors.initials: R
authors.lastname: Gibbs
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Noebels
mesh_terms: D003198:Computer Simulation; D004827:Epilepsy / Q000235:genetics*; D004843:Epistasis, Genetic; D020869:Gene Expression Profiling; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D007473:Ion Channels / Q000235:genetics*; D020125:Mutation, Missense; D009474:Neurons / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D018570:Risk Assessment
chemical_list: D007473:Ion Channels