Mutations in SLC12A5 in epilepsy of infancy with migrating focal seizures.

Stödberg T, McTague A, Ruiz AJ, Hirata H, Zhen J, Long P, Farabella I, Meyer E, Kawahara A, Vassallo G, Stivaros SM, Bjursell MK, Stranneheim H, Tigerschiöld S, Persson B, Bangash I, Das K, Hughes D, Lesko N, Lundeberg J, Scott RC, Poduri A, Scheffer IE, Smith H, Gissen P, Schorge S, Reith ME, Topf M, Kullmann DM, Harvey RJ, Wedell A, Kurian MA

Nat Commun 6 (-) 8038 [2015-09-03; online 2015-09-03]

The potassium-chloride co-transporter KCC2, encoded by SLC12A5, plays a fundamental role in fast synaptic inhibition by maintaining a hyperpolarizing gradient for chloride ions. KCC2 dysfunction has been implicated in human epilepsy, but to date, no monogenic KCC2-related epilepsy disorders have been described. Here we show recessive loss-of-function SLC12A5 mutations in patients with a severe infantile-onset pharmacoresistant epilepsy syndrome, epilepsy of infancy with migrating focal seizures (EIMFS). Decreased KCC2 surface expression, reduced protein glycosylation and impaired chloride extrusion contribute to loss of KCC2 activity, thereby impairing normal synaptic inhibition and promoting neuronal excitability in this early-onset epileptic encephalopathy.

Clinical Genomics Stockholm

NGI Stockholm (Genomics Applications)

NGI Stockholm (Genomics Production)

National Genomics Infrastructure

PubMed 26333769

DOI 10.1038/ncomms9038

Crossref 10.1038/ncomms9038

pii: ncomms9038
pmc: PMC4569694


Publications 9.5.1