Pharmacogenetic studies test how genetic variants affect response to treatment, with the aim of assisting treatment choices to maximise efficacy and minimise side effects. Most progress has been made in identifying rare high-risk variants that increase risk of adverse drug events (for example, abacavir and HLA-B*57:01, carbamazepine and HLA-B*15:02), whilst prediction of treatment efficacy has largely evaded genetic dissection.
