Hi Sue! All of my hematologists thought the flushing was due to polycythemia vera, but without the JAK2 mutation, you're highly unlikely to get a diagnosis. It's complete bullshit. I've had my blood tested for the JAK2 mutation and also had a bone marrow biopsy to check for the mutation, but both came back negative. Something like 95% of people with PV have this mutation so it is now a major diagnostic criteria from WHO. However, check this shit out! I saw a post from another thread here on Mayo Connect where someone mentioned that they had their DNA done through 23andMe and uploaded their raw data to a site called Livewello. Livewello searches through all of your raw DNA data and produces a variant report for you. You can actually get thousands of variant reports. Anyway, I ran a report on my DNA to check for any variants in the JAK2 gene and looky looky...hope this works.