GENETIC-HETEROGENEITY OF HEREDITARY MOTOR AND SENSORY NEUROPATHY TYPE-VI

Charcot-Marie-Tooth disease comprises a heterogeneous group of neurolo gic disorders that share peripheral motor and sensory neuropathy. A cl assification of these disorders was proposed in 1975, defining seven t ypes of hereditary motor and sensory neuropathy. Clinical features of hereditary motor and sensory neuropathy type VI are muscle weakness an d atrophy in leg and hand muscles, leading to progressive disability a nd loss of vision and progressing to blindness due to optic atrophy. H ereditary motor and sensory neuropathy type VI was first reported in 1 879 by Vizioli, who described a kinship in which a father and two sons presented with peroneal muscular atrophy in association with optic at rophy. Since then, at least nine similar cases have been reported: thr ee sporadic cases, two pairs of siblings who were offspring of consang uineous parents, and one pair of siblings who were offspring of unrela ted parents, suggesting autosomal recessive inheritance. Vertical tran smission has been reported only by Vizioli. We present a father and tw o offspring (one boy and one girl) with the above-mentioned characteri stic features of hereditary motor and sensory neuropathy type VI. Vizi oli's kinship and the present family show that hereditary motor acid s ensory neuropathy type VI is a genetically heterogeneous disorder, wit h either an autosomal recessive or autosomal dominant pattern of inher itance.