In contrast to PMP22 overexpression in CMT1A disease, a heterozygous deletion of the PMP22 gene causes hereditary neuropathy with liability to pressure palsies (HNPP) (Nicholson et al., 1994; Adlkofer et al., 1995; Li et al., 2007). Here, PMP22 is linked to hereditary neuropathy with liability to pressure palsies.