Fig. 2

Genotype–phenotype association. a Circos plot illustrating the variable cognitive profile of PCDH19-GCE (n = 155) against age at seizure onset: ≤12 months (n = 124) and >12 months (n = 48). Recurrent variants p.Asn340Ser (n = 17) and p.Tyr366Leufs*10 (n = 23) are highlighted in red and blue, respectively. Axes show the number of individuals in each category. Illustration represents cases where relevant information was available. b Bar graph (±1 SEM) illustrating the association of age at seizure onset and ID severity (values from unadjusted linear model), ***p = 3.090 × 10−7. Cognitive function was scored on a scale: (0) “normal”, (1) “borderline”, (2), “mild ID”, (3) “moderate ID”, and (4) “severe/profound ID”, with higher scores indicating increased ID severity. Mean ID severity was derived by totaling the scores and dividing by the number of individuals in that group