I had a c section and they gave me morphine when the spinal wore off. It did nothing to my delight. I still remember the feeling of being rolled down the hall with zero pain killer, every bump and turn. Delightful. Before I knew any better I also did one of those DNA profiles. My genetics told me this but this was about a year after that happened. You're right though, I'm sure there is an upside to this. I don't actually think it's a defect or mutation. I also metabolize alcohol so quickly that it's almost impossible for me to get drunk like other people do. I'm not a cheap date, at all. I shared this because I recently tried to use Kratom and I was extremely disappointed that it didn't work. It's kind of a duh moment, obviously it wouldn't work for me since morphine doesn't and they both use opiate receptors in the brain. Oh well.