As expected, the reconstituted organoids of "ESGCs + Matrigel" were positive with ESG markers K7 and Na+-K+-ATPase (NKA) but negative with HF markers K27 and K73; otherwise, the reconstituted organoids of "FDKCs + Matrigel" were positive with HF markers K27 and K73, but negative with ESG markers K7 and NKA. This evidence concerns the gene KRT7 and hydrops fetalis.