Genetic or environmental?

We know that regurgitations of menstrual blood occur in 90% of women; so, in that case, why don’t they all have endometriosis?  “Before, we thought that endometriosis developed in women whose macrophages couldn’t break down the blood that had flowed back. Now, we are offering another theory – that we’re on the point of publishing – which says that it is the endometrium in these women that is different and that instead of undergoing necrosis,  and shrinking, the regurgitated cells spread, proliferate and adhere elsewhere, and therefore transform into endometriotic foci. The cause of these modifications is epigenetic.”

We already know that a genetic predisposition plays a role in endometriosis: the daughters of mothers who have this condition are seven times more likely to suffer from it too. Very precise mutations have been discovered and published just recently. But this genetic terrain probably isn’t a sufficient determining factor; epigenetics most certainly have something to do with it. In other words, it is gene expression that is disrupted rather than a defect in the genes themselves.

Thus we come back to fundamental research. With her characteristic energy, Michelle Nisolle is currently running several projects on this theme. “The overall idea is to reveal the environmental influences on the health of women. There is a well-known precedent: that of women who have been exposed to diethylstilbestrol (DES) in utero. We revealed a long time ago that these women developed cervical and vaginal cancer, infertility and anatomical modifications to the uterus. But a recent publication in the New England Journal of Medicine ⁽⁴⁾ shows that, besides these risks, these women also have a higher frequency of miscarriages, breast cancer, early menopause, etc., all phenomena that can be attributed to endocrine dysregulation. Which leads us to suspect the influence of environmental contaminants in the gynaecological sphere, and this is something we’d now like to investigate.”

A multidisciplinary research

Being at the head of a gynaecological and obstetrics university Unit, which includes a large range of pathologies, is obviously a strategic position to launch such research. Blood tests and biopsies carried out on patients will be sent for analysis to the toxicology department of Corinne Charlier, who has developed methods to rapidly detect a relatively large number of known toxic environments.  At the same time, the same approach will be adopted concerning sperm samples taken during male infertility consultations. We know that sperm also suffers from a continuous loss of quality, to a particularly worrying degree in man, compared with other mammals.

(4) Adverse health outcomes in women exposed in utero to diethylstilbestrol, Hoover RN, Hyer M, Pfeiffer RM, Adam E, Bond B, Cheville AL, Colton T, Hartge P, Hatch EE, Herbst AL, Karlan BY, Kaufman R, Noller KL, Palmer JR, Robboy SJ, Saal RC, Strohsnitter W, Titus-Ernstoff L, Troisi R, in N Engl J Med 365 (2011) 1304-14.