This is scarier to insurance companies than to doctors, for obvious reasons.
I just went through the full battery of blood/urine tests for a life insurance application. Imagine how a genetic screen would impact your insurance rates. Would an insurance company risk a long term care policy on someone with known alleles for Alzheimer's? They already jack up the rates if your A1C, fasting glucose or cholesterol numbers are high.
There is as much room for beneficial results. Being aware of alleles that impact sensitivity to specific drug types can be a life saver. There was a vitamin E study that showed great results in some people and little effect in others. Those with great results were getting a supplement for a genetic defect. The ones with little effect didn't have the genetic defect and functioned normally with or without the supplementation.