Unfortunately, no. They do not know what is causing the increase. At first they thought it was a cancer called Polycythemia Vera, but it is not cancer. To make your head spin, it is only polycythemia. I know, right. Haha.
Because the cause is unknown and they do not know if it will transfer to others, the blood cannot be donated. I had hoped it could be, but it would break my heart if I caused someone this sort of pain.
I am so sorry about your uncle. The loss can be horrible to the mind of others. I appreciate your thoughts and you.
Ren