Based on the candidate genes associated with HF development, we found that in the yellow, green, red, brown and turquoise modules (Fig. 6c), the core genes (LAMA5, ACVR1B, EGFR, FZD1, ITFB4, PTCH1, WNT5A, GLI2, LGR4, PTCH2, TGFβ2, LRP4, LRP5, FGF10, TGFβ3, BMPER, SOX10, WNT16, DKK1, TMEM79, BMP4, DSG4, ZDHHC21, SOSTDC1, TP63, RBPJ, FZD3, KRT25, WNT10A, WNT3, BMP7, KRT14, FZD4, and ITGA6) may be involved in the control of the HF development process. Here, FZD3 is linked to hydrops fetalis.