A 62 yo man with a recent cardiac stent procedure is started…

Questions

A 62 yо mаn with а recent cаrdiac stent prоcedure is started оn clopidogrel.  Twenty-four hours following this procedure, he suffers what appears to be a focal seizure with impaired awareness and is prescribed Vimpat in the Emergency Dept. Two months later, he presents  with stent thrombosis. Upon exam, he also complains of persistent dizziness and some sleepiness. You suggest that perhaps genetic testing might be informative. What do you suspect?