In support of this notion, Pten loss in Lgr5+ cells promotes extensive HF neogenesis in the wounds of 5-week-old mice, which otherwise are not capable of regenerating HF; thus, cell signalling activity, such as AKT/β-catenin signalling, in Lgr5+ cells is crucial for HF neogenesis. This evidence concerns the gene LGR5 and hydrops fetalis.