Monica Coenraads interviews Michael Green, MD, PhD of the UMASS School of Medicine about his newly published paper in Proceedings of the National Academy of Sciences. The work was funded, in part, by RSRT. He has identified a number of genes that when disrupted can reactivate the silenced X chromosome in females. Some of these genes lie in pathways that are druggable which makes this work potentially clinically relevant not only for Rett Syndrome but also for other X-linked disorders.
Prof. Green’s paper was covered by SFARI.org. in an article written by Jessica Wright.
Drugs that activate the silent copy of the X chromosome in women may be able to undo the damage from mutations in genes located there. The study, published 2 September in Proceedings of the National Academy of Sciences, offers hope for treating Rett syndrome and other disorders linked to the chromosome1.
One copy of the two X chromosomes women carry is randomly silenced in each cell of the body. This occurs when the chromosome makes small pieces of RNA, called X-inactive specific transcript, or Xist. A cloud of Xist coats the chromosome and blocks its expression.
Female mice lacking Xist die in utero, so X inactivation was thought to be required for survival. The new study suggests otherwise.
The researchers identified 13 genes required for X inactivation. Female mice missing STC1, one of these genes, show expression of genes from both copies of X and have no obvious symptoms.
“The mouse findings suggest that you might be able to survive without X chromosome inactivation,” says lead researcher, professor of molecular medicine at the University of Massachusetts Medical School.