SULT1E1 and endometriosis: In ectopic tissue of patients with ovarian, peritoneal, and deep infiltrating endometriosis, no significant differences in the expression of SULT1E1 was seen at the mRNA level (Smuc et al., 2007, 2009; Colette et al., 2013), while there were significantly higher mRNA levels in ectopic endometrium of deep infiltrating endometriosis, when compared to the normal endometrium (Dassen et al., 2007).