A clinical, genetic and epidemiological study of hereditary motor and sensory neuropathies (HMSN) was performed in the province of Turin, Italy. The patients were allocated to 5 groups, according to genetic and electroneurographic features. The high proportion of males among recessive and sporadic cases in the present series may suggest the existence of a recessive X-linked form of the disease. The crude prevalence rate was 3.18 (+/- 0.72)/100.000 population for all cases. The slow progression rate and the frequently mild symptoms of the disease, already suggested in literature, are confirmed by the analysis of the survival curves of the cases.