Fig. 2

a Schematic representation of the coding sequence of DYRK1A (NM_001396.3) showing the localization of the two de novo mutations identified in this study. b Agarose gel electrophoresis of the RT-PCR products from patient 1 (Pat 1) and a control individual (CTR). A fragment covering exons 5–8 was amplified by RT-PCR (yellow in a). The expected 528 bp PCR product was observed from both patient 1 and the control individual, whereas a smaller PCR product (~240 bp) was only detected in patient 1. A 100 bp ladder was used for reference. c Sequencing of both the wild type (WT) and mutant fragments from patient 1 showing the WT DYRK1A transcript sequence covering exons 6 and 7, and mutant DYRK1A transcript lacking exon 6, resulting in a frameshift and a premature stop codon 22 codons downstream