Ever heard of the Lyon Hypothesis, or the process of Lyonization? Stick with me for a moment, and channel your intro biology class in college. Female mammals have two X chromosomes (XX) but males only have one (XY). In order to equalize this imbalance in dosage, as females are developing, in each of their cells one of the two X chromosomes is randomly turned off, or inactivated. The process of X-chromosome inactivation is the crux of the Lyon Hypothesis. This inactive X chromosome is also called the Barr Body, and the most famous visual example of the process is the female calico cat, which is owes its coloring to the inactivation of different X-linked coat color genes during development.
The lab that I work in studies X-chromosome inactivation, and I am involved in investigating one of the proteins required for the chromosome silencing. Of course, we aren’t the only lab in the world studying this fascinating phenomenon, many other labs are also interested in it, with interests ranging from basic science to understanding X-linked diseases. With this in mind, my advisor helped to organize a scientific conference celebrating the advances in the field, and the 50th anniversary of Mary Lyon describing random X chromosome inactivation. We hosted the conference here in Oxford last week, and it was excellent.
The conference was held at St. Catherine’s college, which isn’t the most magnificent looking, but it does have a huge dining hall, and they are really good at hosting conferences. We managed to pack 50 talks in 3 full days, including a lot of unpublished data which is rare for such a competitive field.
In addition to hearing about the latest research in the form of a talk or at the poster sessions, we held an informal discussion on the banks of the river Cherwell. Editors from popular scientific journals agree to moderate the discussion, and it was a chance for the field to discuss issues and topics with almost all of the major players present. And as an added non-academic bonus, we got to have a great lunch followed by punting on the river. Punts are the wooden boats in the background, and admittedly not easy to use the first time. Especially for uncoordinated scientists.
We also had a really nice catered dinner in the Museum of Natural History. I really enjoyed the setting, because we haven’t been to the museum yet, and it looked really cool at night.
One of the coolest aspects of the meeting for me was meeting and chatting with the pioneers of the field. There was a session one afternoon where many of the early X-inactivation scientists shared their stories, and I found their leaps of understanding to be amazing. We have good molecular tools now to dissect how this process works, but their original observations and discoveries were incredible. None more incredible than the drive behind the woman who jump started the field, Mary Lyon herself.
Here is Mary enjoying a glass of Pimms. I was amazed how active she still is, (she even goes into the lab from time to time) and it really was a privilege to be able to meet her. An appreciation for the history of science was impressed upon me by my graduate school advisor Dan, who enjoyed reading the classical Drosophila papers from 90 years ago. It doesn’t get much better than meeting the founder of the field.
During that special historical session, one of the early researchers in the field made a joke that Susumo Ohno gets a law, but in fact, 50 years of research has proven Mary Lyon’s hypothesis to be more of a law than Ohno’s. And so it was, we agreed that the Lyon Hypothesis should be renamed to Lyon Law. Congrats Mary!