The TNNI3 gene encoding cardiac troponin I (cTnI) is located at 19q13.4 in the human chromosomal genome.

[8] Early embryonic heart expresses solely slow skeletal muscle TnI.

cTnI begins to express in mouse heart at approximately embryonic day 10, and the level gradually increases to one-half of the total amount of TnI in the cardiac muscle at birth.

[15] The half-life of cTnI in adult cardiomyocytes is estimated to be ~3.2 days and there is a pool of unassembled cardiac TnI in the cytoplasm.

[34] An increased level of serum cTnI also independently predicts poor prognosis of critically ill patients in the absence of acute coronary syndrome.