Major advances in research over the last two years have determined that FSHD is caused by the aberrant expression of the DUX4 gene in skeletal muscle. DUX4 is normally expressed in germline cells and early development, but tissues in the adult completely suppress the expression of DUX4. In FSHD the suppression is incomplete and DUX4 is expressed in mature skeletal muscle. Recent work in the Tapscott lab has shown that DUX4 normally regulates the expression of germline and stem cell genes and that the mis-expression of DUX4 in skeletal muscle activates that expression of these early developmental genes. Work recently funded by Friends of FSH Research will use these findings to develop the components necessary to identify drugs that prevent the DUX4 expression and/or DUX4-induced damage in muscle cells. The Tapscott lab plans to develop several ways to measure DUX4 expression and toxicity, and then perform tests to see how well each can be used for a large-scale screen of possible drugs. As the tests are validated it is anticipated that pharmaceutical companies might adopt them to screen their extensive libraries of drug-like compounds.
— Stephen Tapscott