WNT4 and SERKAL syndrome: Mutations in the human WNT4 gene are associated with Mayer–Rokitansky–Kuster–Hauser–Biason–Lauber (MRKHBL) and female SEx Reversal and dysgenesis of Kidneys, Adrenals, and Lungs (SERKAL) syndromes, which involve severe defects in the female reproductive tract but the underlying molecular mechanisms that distinguish between a normal and a pathological uterus are still for the most part poorly understood (15–20).