A cluster headache family with possible autosomal recessive inheritance

Until the early 1990s, cluster headache (CH) was considered a sporadic disorder, with a prevalence of 69 per 100,000.1 The presence of CH in monozygotic twins2 and in first- and second-degree relatives3 suggested that genetic factors might be involved. Based on a mailed questionnaire, the prevalence of familial CH was 7%, and based on personal examination of alleged familial cases, it was 30%.3 A large epidemiologic study suggested autosomal dominant inheritance can be involved in some families.4 The current study describes a large kindred in which an autosomal recessive model could be involved. The pedigree (figure) includes four related families from the Naples area (southern Italy). The proband (IV-1), diagnosed in March 2000, referred other relatives possibly affected. All living members were interviewed by telephone, and all possibly affected members were evaluated by a neurologist experienced in CH. Clinical information about deceased individuals, obtained from their descendants, allowed us to exclude CH. Figure. Pedigree of a large kindred of four related families in which eight members …