What I found was that half the people with diabetes develop PN. There are many, many other causes for PN including inherited ones. Good site listing it:

http://www.mayoclinic.org/diseases-c...s/con-20019948

There are DNA blood tests that can rule in or out some of these problems. Yes, some people will never know what the cause of their PN is. It can be very complicated as most of us know.

Yes, I know that I could do a search on your name to read about what you have been through.