@1995victoria

You can believe me or not. I am a PhD molecular biologist and geneticist who used to work in the molecular lab of a hospital, where we did things like sequencing tumors for mutations and blood samples for JAK2 V617F. I am very experienced in reading research papers like this. I have run a research lab as well.

Obviously I'm also an anonymous person on the internet who could be misrepresenting things. But I don't know why anyone would bother with making up stories about JAK2.

Your doctor will tell you the same thing if s/he is willing to discuss it at all. This kind of misconception is the reason doctors don't like patients consulting Dr. Google.

@1995victoria

The Cancer Genome Atlas program (TCGA) was a multi center project to sequence the DNA of hundreds of samples of virtually every cancer type. (They do not seem to have done MPNs). They did sequence many endometrial cancers and determined which genes were mutated at statistically significant frequencies. There's a nice graphical summary at tumorportal.org. Click on UCEC in the blue section at the top. The next page shows the most commonly mutated genes on the left and has individual patient samples across the top. It lists genes that show statistical significance at the bottom. JAK2 is not among them.

I went and read the beginning of that Chinese lab's paper, and it's pretty terrible. They note that JAK2 is mutated in cancers that also have a mutation in POLE. That's not a big surprise. What POLE mutations do is that they cause the cell to make mistakes while copying its DNA. So POLE mutant cancers have mutations absolutely all over the place, in JAK2 and in many other genes. You can see that on the tumorportal graphic. POLE is the 24th gene on the left, and if you follow that row across, you can see that many specimens with POLE mutations also have many other mutations up and down the graphic. These are considered "passenger mutations", meaning that they're there because the cancer is sloppy at copying its DNA, but that the mutations probably don't contribute to the behavior of the cancer.

If you're interested in looking at more, and more recent, datasets of mutation profiles of cancer samples, they can be found at cbioportal.org.