Wild-type and Wnt7a null female embryos were collected at E13.5 and E14.5. Three biological replicates for each timepoint were obtained, for a total of 12 biological samples. Tissue samples were fixed in 4% PFA overnight at 4oC, embedded in paraffin, sectioned at 5 um, and a section from each sample was placed on a single Fisherbrand ColorFrost Plus microscope slide in an area that was 35.3 mm by 14.1 mm. The slide was sent to NanoString Technologies, Inc. (Seattle, WA). NanoString GeoMx® Digital RNA Spatial Profiling hybridize to mRNA with DNA probes that are conjugated to unique photo-cleavable oligonucleotides barcodes by controlled ultraviolet illumination. The released barcode oligonucleotides are subject to the sequencing