Patients with deficiency of C8 suffer from recurrent neisserial infections, predominantly with meningococcus infection of rare serotypes. Most such patients are discovered among those having their first episode of meningitis at ages older than 10 years (Ross and Densen, 1984). Two types of inherited C8 deficiency have been reported in humans: type I (613790), in which only C8 alpha (C8A, 120950) and C8 gamma (C8G; 120930) are deficient, and type II, in which only C8 beta is deficient (Marcus et al., 1982; Tedesco et al., 1983). The 2 types are clinically indistinguishable (Ross and Densen, 1984).

Patients with deficiency of C8 suffer from recurrent neisserial infections, predominantly with meningococcus infection of rare serotypes. Most such patients are discovered among those having their first episode of meningitis at ages older than 10 years (Ross and Densen, 1984). Two kinds of inherited C8 deficiency have been reported in humans: type I (C8D1), in which only C8 alpha and C8 gamma (C8G; 120930) are deficient, and type II (C8D2; 613789), in which only C8 beta (C8B; 120960) is deficient (Marcus et al., 1982; Tedesco et al., 1983). The 2 types are clinically indistinguishable (Ross and Densen, 1984).