R913C of SETD1A affects cortical development. A–B Examples of cortical migration in control and SETD1A WT overexpression groups. C Quantification of data as in panels A and B. Percentages of GFP-positive cells in the superficial, middle, and deep layers of cortex. D–E Examples of cortical migration in control and SETD1A R913C overexpression groups. F. Quantification of data as in panels D and E. Percentages of GFP-positive cells in the superficial, middle, and deep layers. *P = 0.0392, ***P = 0.0003 (unpaired t test). Scale bars, 200 μm.