For example, a previous study on mouse models with ovarian FOXL2 gene deletion showed that FOXL2+/− mice have a normal phenotype, FOXL2+/+ mice have a similar phenotype as patients with human blepharophimosis syndrome, and FOXL2−/− mice exhibit narrow eye slits and premature ovarian failure (Baron et al., 2005). Here, FOXL2 is linked to primary ovarian failure.