[Hereditary neuropathy with liability to pressure palsies caused by 17p11.2 chromosome deletion]

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant disorder characterised by recurrent mononeuropathies. Electrophysiological studies reveal slowed conduction velocity in peripheral nerves. The main histopathological findings are focal thickenings of myelin-tomaculae. In most cases HNPP is associated with a deletion within PMP-22 (peripheral myelin protein; PMP) gene on chromosome 17p11.2. The gene penetration is almost complete but the expression may be variable. DNA analysis is of practical importance in diagnosing HNPP especially in sporadic cases and also in individuals without clinical and electrophysiological signs of neuropathy. We present the first Polish family with HNPP, in which the genetic defect has been confirmed by DNA analysis.