Two siblings, whose parents were 1st cousins, developed progressive changes similar to those described by Refsum under the name "heredopathia atactica polyneuritiformis". Retinitis pigmentosa and night blindness occurred early, followed by chronic polyneuritis with weakness, wasting and sensory changes in the limbs, ichthyosis, progressive nerve deafness, and a very high cerebrospinal fluid protein. The history and findings are reviewed and the family pedigree is presented.