Author response image 2. UMAP visualisation of gene expression in naïve cells following TGFβ inhibition, as measured by 10X scRNA-seq.

The plots show that trophoblast markers such as GATA3 are uniformly expressed in ‘Cluster E’, but markers of syncytiotrophoblast (STB) such as SDC1 and extravillous trophoblast (EVT) such as MMP2 are expressed in only a small number of cells in this population (indicated by the arrows).