E10.5 FNP and MxP bulk tissue from three control and three Tfap2Δ/NCKO littermates were processed for RNA-seq as previously described (Van Otterloo et al., 2016 (link)). After PCR-genotyping, samples stored in RNAlater (ThermoFisher) were processed for RNA (Norgen Biotek) and further purified with the RNAeasy kit (Qiagen). mRNA quality was determined with DNA Analysis ScreenTape (Agilent Technologies), and cDNA libraries were generated using the Illumina TruSeq Stranded mRNA Sample Prep Kit (Illumina). Samples were sequenced on the Illumina HiSeq2500 platform as 150-bp single-end reads. Library construction and sequencing was carried out by the Genomics and Microarray Core on the University of Colorado Anschutz Medical Campus.