The Corus CAD test considered as a medically diagnostic option for patients presenting with symptoms suggestive of obstructive CAD. CAD can also cause atypical angina symptoms. Current technologies of CAD are: noninvasive cardiac imaging results in radiation exposure while invasive coronary angiography increases the patient’s radiation exposure and carries additional risks for adverse events. The Corus CAD gene expression test is clinically useful in non-diabetic patients with typical or atypical symptoms suggestive of CAD helps to determine DNA sequences and can help estimate a person’s lifetime risk of developing disease in the future. Clinical studies of CAD describes analytic validity—a measure of reproducibility, clinical validity—test performance in excluding the diagnosis of obstructive CAD, clinical utility—long-term outcomes, gender-specific analysis, clinical utility—the change in medical decision-making and recommended clinical pathway employing the Corus CAD test. The clinical utility studies showed that low Corus CAD scores are associated with decreased downstream health care resource utilization in both the primary care and cardiology setting.