A 22-year-old man had polyneuropathy, facial dysmorphia, atopia and multiple lipomatosis. His mother had neuropathy but not lipomatosis as two of her first cousins. The proband's grandmother had multiple lipomatosis as her own mother and a sister of her mother, but they didn't have neuropathy. This family is an example of a dominant syndrome the principle features of which are polyneuropathy. Variable expression could account for the phenotypic differences, combined with multiple lipomatosis.