Identification of TSC2 Mutation in Twin Patients with Tuberous Sclerosis Complex

Objective: To identify gene mutations in twin patients with tuberous sclerosis complex( TSC) and their parents. Methods: All the coding region,including all exons and exon-intron boundaries of TSC2 were amplified by polymerase chain reaction. The products were analyzed by direct DNA sequencing. The gene of their parents and 500 unrelated healthy Chinese individuals were analysed by RFLP( restriction fragment length polymorphism) to search for the mutation and to test whether the mutation co-segregates with the disease. Results: One nucleotide G in 2032TSC2 was substituted by A,which caused a missense mutation p. A678T in both of the twin patients. RFLP results showed that their father and three of the 500 normal individuals carried the c.G2032A mutation. Conclusion: A novel missense mutation p. A678T was identified in Chinese patients with Tuberous Sclerosis Complex,which expand the mutation spectrum of TSC2 mutations which showed the correlation with TSC.