Curious if your doctors are tracking your JAK2 Variant Allele Frequency (VAF) on a regular basis? I was diagnosed in January 2026 with ET, and my VAF is still low (18)- which sounds good. However my VAF jumped from 12 to 18 in 6 weeks. The first was from a blood test, the later was from a bone marrow biopsy. My Dr said VAF is not something to be concerned with or that he will track. He instead will watch WBC, RBC, Hgb and platelets for signs of progression or trouble.