Hereditary neuropathy with liability to pressure palsies and inherited brachial plexus neuropathy--two genetically distinct disorders.
OBJECTIVE
To determine whether hereditary neuropathy with liability to pressure palsies (HNPP) and inherited brachial plexus neuropathy (IBPN) are genetically distinct disorders and to evaluate the usefulness of fluorescence in situ hybridization (FISH) for diagnosing HNPP in individual patients.


METHODS
We studied representative metaphases from patients with HNPP and IBPN with use of FISH and a DNA probe.


METHODS
With use of FISH, 14 persons from 4 unrelated families with HNPP and 7 members from 3 unrelated families with IBPN were studied. We used a DNA probe that hybridizes to chromosome 17p11.2 in an area thought to be deleted in HNPP.


RESULTS
Each participant in this study who had HNPP showed deletion of this chromosome site. Each of the 10 control subjects and 7 patients with IBPN showed normal fluorescent signals on both number 17 chromosomes.


CONCLUSIONS
These results demonstrate that HNPP and IBPN are genetically different. FISH with this probe is a sensitive and specific method for detecting the chromosomal deletion in individual patients without the use of family studies or linkage analysis.
Windebank
A J
AJ
Department of Neurology, Mayo Clinic Rochester, Minnesota 55905, USA.
Schenone
A
A
Dewald
G W
GW
D020968:Brachial Plexus Neuritis / Q000235:genetics*; D002872:Chromosome Deletion; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D015342:DNA Probes; D005260:Female; D018734:Genes, erbB-2 / Q000235:genetics; D015417:Hereditary Sensory and Motor Neuropathy / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008677:Metaphase; D010243:Paralysis / Q000235:genetics
D015342:DNA Probes