WNT4 and Mayer-Rokitansky-Kuster-Hauser syndrome: In particular, WNT4 is known to be essential for the development of the female reproductive tract and heterozygous mutations in WNT4 have been associated with a distinct clinical entity of MRKH (Biason-Lauber et al., 2004, 2007; Philibert et al., 2008, 2011).