Wnt4 has also been studied with regard to its function in the development of the Müllerian duct, as mutations in or the absence of Wnt4 in the Müllerian mesenchyme results in vaginal agenesis (Biason-Lauber et al., 2004; Biason-Lauber et al., 2007; Prunskaite-Hyyryläinen et al., 2015; St-Jean et al., 2019), a deformity that is usually diagnosed in MRKH patients. The gene discussed is WNT4; the disease is Mayer-Rokitansky-Kuster-Hauser syndrome.