Troponin T type 2 (cardiac), also known as TNNT2, is the tropomyosin-binding subunit of the troponin complex, which is located on the thin filament of striated muscles and regulates muscle contraction in response to alterations in intracellular calcium ion concentration. Mutations of this gene may be associated with mild or absent hypertrophy and predominant restrictive disease, with a high risk of sudden cardiac death.