However, for example, closer inspection of genes involved in the “cocaine addiction” pathway reveals that they are also involved in cardiac regulation: glutamate receptor subunit (GRIN2C) is involved in regulating calcium transport in heart tissues (94); activating transcription factor 4 (ATF4) is a transcription factor for redox regulators in cardiomyocytes (95). The gene discussed is ATF4; the disease is cocaine dependence.