Definition:

Hereditary neuropathy with liability to pressure palsy (HNPP) is a rare autosomal dominant peripheral neuropathy characterized by compressive focal neuropathies and an underlying sensorimotor demyelinative polyneuropathy. HNPP is caused by a peripheral myelin protein (PMP22) gene deletion. PMP22 is duplicated in Charcot-Marie-Tooth disease type 1A (CMT1A). The other identified underlying genetic defects in HNPP are point mutations in PMP22 that lead to premature or delayed translation.