A New Point Mutation in the PMP22 Gene in a Family Suffering From Atypical HNPP.
Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant inherited disorder commonly presenting with acute-onset, non-painful focal sensory and motor mono neuropathy. In 80% of cases, the genetic defect is a 1.5 Mb deletion on chromosome 17p11.2, including PMP22. Only few cases of partial deletion and point mutations in PMP22 are involved in HNPP. We investigated a 62-years-old man with lower limb plexopathy first considered as Garland's syndrome. A month later, his 29 years old son also consulted for paresthesia on the peroneal nerve.Targeted sequencing of the PMP22 gene identified a c.370delT (p.Trp124Glyfs*31) in both affected patients.We report a new PMP22 point mutation associated with an atypical clinical phenotype of HNPP, a painful plexopathy of the lower limb worsenen by diabetes and a mere paresthesia, but a typical ENMG. This study illustrates the large spectrum of the disease, and emphasizes the importance of a complete ENMG and family history.
['Benquey|T|T|', 'Fockens|E|E|', 'Kouton|L|L|', 'Delmont|E|E|', 'Martini|N|N|', 'Levy|N|N|', 'Attarian|S|S|', 'Bonello-Palot|N|N|']
D000328:Adult D001176:Arthrogryposis D015417:Hereditary Sensory and Motor Neuropathy D006801:Humans D008297:Male D008875:Middle Aged D009185:Myelin Proteins D010375:Pedigree D010641:Phenotype D017354:Point Mutation
point mutations PMP22 gene HNPP phenotypic heterogeneity