title: A new single-nucleotide deletion of PMP22 in an HNPP family without recurrent palsies.
abstract: In this study we describe four patients from the same kindred who were affected by an autosomal-dominantly inherited peripheral neuropathy. They presented an unusual combination of clinical, electrophysiological, and pathological findings in association with a new mutation of the PMP22 gene. Clinically, three patients had carpal tunnel syndrome symptoms and one patient had late-onset peroneal atrophy. Motor and sensory nerve conduction velocities were reduced without focal slowing at entrapment sites. Nerve biopsy disclosed diffuse hypomyelination with focal thickening of the myelin sheath in some fibers. Sequence analysis of the PMP22 gene showed a single-nucleotide deletion (227delG) in the affected patients. This mutation, which has not been reported previously, leads to an open reading frame shift and probably to a truncated and unstable PMP22 protein. We conclude that this novel 227delG mutation of PMP22 gives a mild form of hereditary neuropathy with liability to pressure palsy with atypical clinical and electrophysiological findings.
authors.affiliation: Istituto di Neurologia, Università Cattolica del Sacro Cuore, Pol. A Gemelli Largo Gemelli 8, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Luigetti
authors.forename: Amelia
authors.initials: A
authors.lastname: Conte
authors.forename: Francesca
authors.initials: F
authors.lastname: Madia
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Mereu
authors.forename: Marcella
authors.initials: M
authors.lastname: Zollino
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Marangi
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Pomponi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Liberatore
authors.forename: Pietro Altilio
authors.initials: PA
authors.lastname: Tonali
authors.forename: Mario
authors.initials: M
authors.lastname: Sabatelli
mesh_terms: D000368:Aged; D004252:DNA Mutational Analysis; D005192:Family Health; D005260:Female; D017353:Gene Deletion; D015417:Hereditary Sensory and Motor Neuropathy / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009185:Myelin Proteins / Q000235:genetics*; D009431:Neural Conduction / Q000235:genetics; D017384:Sequence Deletion / Q000235:genetics*
chemical_list: D009185:Myelin Proteins; C073687:PMP22 protein, human