The question of genetic heterogeneity in tuberous sclerosis (TSC) was addressed by genetic linkage studies in eight affected families using nine polymorphic markers (EFD126.3, MCT136, ABO, ABL, AK1, and MCOA12 from distal 9q, and PBGD, MCT128.1, and 1CJ52.208M from distal 11q).
Two-point linkage analysis and multilocus linkage analysis were used to evaluate linkage between tuberous sclerosis and the markers ABO, MCT136, and AblK2.