PLP1 and Alexander disease: Current AxD mouse models do not recapitulate myelin deficits that are present in certain forms of human AxD [8], and we observed no differences in expression levels of transcripts encoding two myelin components, Plp1 (proteolipid protein (myelin) 1) and Mog (myelin oligodendrocyte glycoprotein), in PEX-treated WT or AxD mice (Additional figure 4a-d).