Especially intriguing is that many of the biological functions of GDF15 fit with the HF phenotype, from activation of hypothalamic neurons [39] leading to anorexia with drastic weight loss and cachexia [63], to direct catabolic effects on skeletal muscle [12] and a negative impact on Growth hormone-Insulin like Growth Factor-1 axis (GH-IGF1 axis) [81]. The gene discussed is GDF15; the disease is hydrops fetalis.