PMP22 and Charcot-Marie-Tooth disease type 1A: In order to test if progesterone can modulate the progressive neuropathy caused by moderate overexpression of PMP22, Sereda and collaborators [88] administrated daily subcutaneous injections of progesterone and the progesterone antagonist, onapristone, to a transgenic rat model of CMT1A during 7 weeks and showed that onapristone reduced PMP22 mRNA by 15%, resulting in clinical and neuropathological improvement.