BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal, dominantly 
inherited neurocutaneous syndrome characterized by a wide range of neurological 
abnormalities, tumors of different organs, and variable clinical symtomatology 
and severity. TSC is caused by mutations in either of two tumor suppressor 
genes: TSC1 or TSC2. The aim of this study was to analyze the clinical picture 
of TSC in patients with an identical TSC2 mutation. We tried to discover to what 
extent we may expect variability in the clinical set of symptoms in patients 
with identical mutation of TSC2 gene.
MATERIAL/METHODS: Mutations were identified in 100 of 170 cases. There were only 
4 patients with the same type of TSC2 mutation: 5238-5255 del 18bp, del 1746 
HIKRLR. Their ages were 1.5, 9, 9, and 10 years. A standardized clinical 
assessment of TSC symptoms was used.
RESULTS: Epilepsy, depigmented spots, and periventricular calcification and 
cortical tubers were diagnosed in all the 4 patients, cardiac rhabdomyoma and 
angiomyolipoma of the kidneys in 3, and mental retardation and forehead fibroma 
in 2. Other symptoms occurred rarely or were absent. There was variability in 
TSC symptoms in patients with the identical type of TSC2 mutation. The main 
symptoms were present in all or in the majority of patients. Clinical picture 
also differed with the age of patient.
CONCLUSIONS: There are many influencing factors contributing to the diversity of 
the clinical picture and pathology of TSC. Obviously, a greater number of cases 
are needed for further analysis and more precise conclusions.