By screening blood samples from patients with autosomal dominant retinitis pigmentosa, we found in one of the families a rhodopsin mutation (Pro-267-Leu), which segregates with the disease in two affected and five unaffected family members. Here, we present the results of the clinical evaluation of the family, including full-field electroretinography from the two affected family members. A 25-year-old family member with the mutation had an almost normal electrophysiological retinal response. The patient's father, who was also heterozygous for the mutation and had mild subjective symptoms of retinitis pigmentosa, demonstrated a substantially preserved retinal function. Our results suggest that the Pro-267-Leu rhodopsin mutation is associated with a very mild phenotype of retinitis pigmentosa. Young patients with the disease may have minimal pathological changes in the electroretinogram and some patients with few symptoms may be affected without acquiring a diagnosis of eye disease.