Objective. To identify the features of brain involvement and to characterize the genetic causes of tuberous sclerosis (TS) in patients in the Republic of Bashkortostan. Material and methods. A retrospective analysis of data on patients with TS registered with geneticists of the Republican Medical Genetic Center for the period from 2012 to 2025 was performed. Results. The prevalence of TS in the republic was 2.12 per 100.000 population. Subependymal giant cell astrocytoma was detected in 19%, epilepsy in 67%, subependymal hamartomas in 66%, and cortical tubers in 43% of patients. Cognitive deficits were present in 47% of patients, while autism spectrum disorders were found in only 1%. Mutations were identified in the TSC1 gene in 5 patients, the TSC2 gene in 19 patients, and extended deletions of the TSC2 gene in 4 patients. Discussion. TS prevalence in the region is 5.24 times lower than the global average. The frequencies of cortical tubers, subependymal nodes, cognitive deficits, and autism spectrum disorders are also significantly lower than those reported in international meta-analyses. No data were available on behavioral disorders or attention-deficit hyperactivity disorder. Five TSC1 gene mutations (three de novo) and 19 TSC2 gene mutations (one de novo) were reported. Eight patients received targeted therapy. Conclusion. Raising awareness of TS among physicians in all specialties is essential to ensure comprehensive case reporting. Genetic confirmation of TS enables effective treatment with mTOR inhibitors. All TS patients should consult a psychiatrist and psychologist for the diagnosis and management of intellectual disability, autism spectrum disorders, and behavioral disorders.
R.N. Mustafin (2026) studied this question.