To examine whether differential expression of Fat4 and Dchs1 could contribute to PCP in the sternum, the expression of Fat4 and Dchs1 was determined by immunolocalisation at E12.5 and E13.5, and their expression levels were quantified against either N–K-ATPase or β-catenin (Fig. 5a,c,e,g,i). This evidence concerns the gene FAT4 and pneumocystosis.