News Finding: The degree of mental disability and related problems was greater in the latter group.
Paper Finding: Comparing the allele frequency of the 6 KCNA2 nonsynonymous variants in our validation cohorts (6/(354 × 2); excluding the first mutation encoding p.Pro405Leu detected in the discovery cohort of 33 patients) with those of missense and nonsense variants reported in the largest available control database (ExAC; 144/122,828) showed a significant enrichment of KCNA2 variants in our patient cohorts using Fisher's exact test (P = 2.6 × 10 −4 ).
News Context: For patients with increased function, however, epileptic seizures began even earlier and recurred into adulthood. The degree of mental disability and related problems was greater in the latter group. For patients whose potassium flows are too high, there is an immediate treatment option in the form of 4-aminopyridine, an approved drug which specifically blocks the relevant ion channel.
Paper Context: Similarly, patient 7 carrying the de novo mutation c.890G>A (encoding p.Arg297Gln) presented with a more severe phenotype consisting of moderate intellectual disability, moderate to severe ataxia and pharmacoresistant seizures. Comparing the allele frequency of the 6 KCNA2 nonsynonymous variants in our validation cohorts (6/(354 × 2); excluding the first mutation encoding p.Pro405Leu detected in the discovery cohort of 33 patients) with those of missense and nonsense variants reported in the largest available control database (ExAC; 144/122,828) showed a significant enrichment of KCNA2 variants in our patient cohorts using Fisher's exact test (P = 2.6 × 10 −4 ). Further statistical evidence is provided in the Supplementary Note.