PMP22 Gene –Associated Neuropathies: Phenotypic Spectrum in a Cohort from India

AbstractReports of spectrum of clinical manifestations inPMP22 gene –associated neuropathies (duplication/mutations) are scarce. To identify the frequency ofPMP22 gene variations and establish their genotype-phenotype correlation. Patients with suspected genetic demyelinating neuropathy (n = 128) underwent evaluation for copy number variations and point mutations inPMP22 gene by multiplex ligation-dependent probe amplification (MLPA) and direct sequencing respectively. Of these, only 27 patients (M:F:19:8) from 18 families hadPMP22 gene –associated neuropathy; they were subsequently analyzed for genotype-phenotype correlation. Twenty-five patients hadPMP22 duplication while two patients hadPMP22 missense mutations (p.A114V and p.L80P). Age at onset of neuropathy ranged from infancy to 63  years and symptom duration ranged from 2 to 32 years. Cranial nerve dysfunction in the form of ptosis, ophthalmoplegia, bifacial weakness, and sensorineural hearing loss was observed in addition to a number of systemic features. Three patients were asymptomatic. All except one patient were ambula nt. Velocity of median nerve and amplitude of evoked motor responses from common peroneal nerve were significantly reduced in male patients. There was significantly worse disability in the late-onset group as compared with the early-onset group. Otherwise, the mean age at onset, frequency of skeleta l deformities, patterns of motor weakness, muscle stretch reflexes, sensory impairment, dis...

Source: Journal of Molecular Neuroscience - January 27, 2020 Category: Neuroscience Source Type: research