Gene regulation plays a role in the interpretation of molecular genetic tests.  Because several complex factors affect genes and traits, it is often difficult to predict the likelihood of developing a genetic disease, even when a complete DNA sequence is obtained from all the genes known to influence the disease.  However, by taking into consideration all available genetic and environmental information, a medical professional should be able to state if a person is at low risk, average risk, high risk, or very high risk for genetic disease development.