Some trials looked promising (e.g., L-serine for HSAN1 and PTX3003 for CMT1A) and will require close monitoring in the future, whereas others showed relatively stable nerve conduction studies upon treatment (e.g., DHA for SCA 38, rhASA for MLD) and warrant longer follow-ups and/or comparisons to natural history cohorts to assess the effects on neuropathy. This evidence concerns the gene PMP22 and neuropathy.