Figure 1.

Family Pedigree

Four-generation pedigree of the Spanish family including the dizygotic twin pair concordant for narcolepsy-cataplexy in the third generation; the distribution of the disorder indicates an autosomal-dominant transmission of the disease-causing gene. The family consists of 13 (12 living) family members affected with narcolepsy-cataplexy. Note that individual III-3 did not fulfill the full diagnostic criteria though the clinical characteristics of this person could not exclude the possibility of narcolepsy-cataplexy. Seven family members were also affected with obesity and four with type 2 diabetes. Individuals III-5 and III-10 (as well as II-1) were diagnosed for all three conditions.