On Monday, April 23, a symposium titled Impact of Environmental Estrogens and Androgens on Human and Animal Health and Reproductive Function convened at Experimental Biology. Hugh S. Taylor, MD of Yale presented an elegant talk on environmental estrogens and disorders of the reproductive tract. One point he made provided what I consider an elegant explanation for how exposure to diethylstilbestrol (DES) in utero could produce weird vaginal tumors many years down the line.
Exposure to DES also produces abnormal reproductive anatomy at the histological level. Turns out normal mullerian development into the female reproductive organs depends on orderly segmental expression of Hox genes, which have estrogen-response elements. As shown in his talk (free full text here), DES exposure shift their expression segments posteriorly (see figure). This shift means that glandular cells normally confined to the uterus end up in the vagina. These cells seem more vulnerable to carcinogenic forces that the usual epithelial cells, and displacing them into the vagina offers them exposure to carcinogenic hits. Thus, these women end up with vaginal adenocarcinoma because they have "adeno" cells in their vaginas.
The other study that you may have heard about, especially if you follow me or @scicurious on twitter involves anogenital length and fetal androgen exposure. Yes, Sci had joined me in the session and we had a blast tweeting the taint! I have Storified the encounter below for posterity (Hey, Nobel Committee, why don't you have an award for meeting tweeting?).
[<a href="http://storify.com/PHLane/it-ain-t-nothing-else-it-tainttweets" target="_blank">View the story "It ain't nothing else...it #TaintTweets" on Storify</a>]