Previous histological analyses described Inha KO tumours as undifferentiated gonadal stromal tumours derived from cells of the Sertoli cell lineage (Matzuk et al., 1992; Matzuk et al., 1994) that are positive for GATA4 (Sertoli cell nuclei) (Haverfield et al., 2017). The gene discussed is INHA; the disease is neoplasm.