Clinical features of patients with JAK2 R564 variants
| Patient no. . | 1 . | 2 . | 3 . | 4 . | 5 . | 6 . | 7 . | 8 . | 9 . | 10 . | 11 . | 12 . |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diagnosis | ET | CLL | ET | ET | ET | ET | CLL | PV | PV | MGUS | PV | AML |
| Age, y | 29 | 51 | 2 | 53 | 49 | 45 | 70 | 73 | 28 | 75 | 61 | 50 |
| Sex | F | M | M | F | F | F | F | M | M | M | M | M |
| Race | Multiracial | Black | Multiracial | White | White | White | White | White | Unknown | Black | White | White |
| JAK2 R564 (VAF) | Q (51%) | Q (51%) | Q (het∗) | L (51%) | L (49%) | L (52%) | L (51%) | L (52%) | L (52%) | L (50%) | L (94%) | L (49%) |
| JAK2 R564X confirmed as germ line | Yes | Yes | Yes | Yes | Yes | No | No | No | No | No | No | No |
| JAK2 V617F (VAF) | No | No | No | No | No | No | No | Yes (11%) | No | No | Yes (88%) | No |
| White blood cell count, ×103/μL | 10.7 | 14.1 | 10.1 | 6.9 | 6.5 | 8.8 | NA | 16.1 | NA | 15.5 | 25.6 | 21.3 |
| Hemoglobin, g/dL | 13.7 | 15.2 | 12.7 | 13.9 | 13.5 | 14.2 | NA | 16.4 | 17.2 | 10.3 | 16.2 | 12.2 |
| Platelet count ×103/μL | 575 | 400 | 503 | 519 | 442 | 438 | NA | 446 | 375 | 75 | 352 | 308 |
| History of thrombosis | PE | No | No | No | No | No | NA | No | No | No | DVT, CRVO | SVT, PVT |
| Splenomegaly | No | No | No | No | No | No | NA | No | No | No | Yes | Splenectomy |
| MPN-SAF TSS | 38 | 34 | NA | 0 | 0 | 53 | NA | NA | 29 | NA | NA | NA |
| Family no. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ||
| Family history of cytosis/MPN | ET | ↑Plts | No | PV | NA | No | No | No | No | No | ||
| Family history of HM | CLL | No | NHL | LGL, lymphoma, leukemia | NA | No | No | No | No | Leukemia | ||
| Family history of thrombosis | PE | DVT | DVT, CVA | No | NA | No | No | No | No | No |
| Patient no. . | 1 . | 2 . | 3 . | 4 . | 5 . | 6 . | 7 . | 8 . | 9 . | 10 . | 11 . | 12 . |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diagnosis | ET | CLL | ET | ET | ET | ET | CLL | PV | PV | MGUS | PV | AML |
| Age, y | 29 | 51 | 2 | 53 | 49 | 45 | 70 | 73 | 28 | 75 | 61 | 50 |
| Sex | F | M | M | F | F | F | F | M | M | M | M | M |
| Race | Multiracial | Black | Multiracial | White | White | White | White | White | Unknown | Black | White | White |
| JAK2 R564 (VAF) | Q (51%) | Q (51%) | Q (het∗) | L (51%) | L (49%) | L (52%) | L (51%) | L (52%) | L (52%) | L (50%) | L (94%) | L (49%) |
| JAK2 R564X confirmed as germ line | Yes | Yes | Yes | Yes | Yes | No | No | No | No | No | No | No |
| JAK2 V617F (VAF) | No | No | No | No | No | No | No | Yes (11%) | No | No | Yes (88%) | No |
| White blood cell count, ×103/μL | 10.7 | 14.1 | 10.1 | 6.9 | 6.5 | 8.8 | NA | 16.1 | NA | 15.5 | 25.6 | 21.3 |
| Hemoglobin, g/dL | 13.7 | 15.2 | 12.7 | 13.9 | 13.5 | 14.2 | NA | 16.4 | 17.2 | 10.3 | 16.2 | 12.2 |
| Platelet count ×103/μL | 575 | 400 | 503 | 519 | 442 | 438 | NA | 446 | 375 | 75 | 352 | 308 |
| History of thrombosis | PE | No | No | No | No | No | NA | No | No | No | DVT, CRVO | SVT, PVT |
| Splenomegaly | No | No | No | No | No | No | NA | No | No | No | Yes | Splenectomy |
| MPN-SAF TSS | 38 | 34 | NA | 0 | 0 | 53 | NA | NA | 29 | NA | NA | NA |
| Family no. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ||
| Family history of cytosis/MPN | ET | ↑Plts | No | PV | NA | No | No | No | No | No | ||
| Family history of HM | CLL | No | NHL | LGL, lymphoma, leukemia | NA | No | No | No | No | Leukemia | ||
| Family history of thrombosis | PE | DVT | DVT, CVA | No | NA | No | No | No | No | No |
Clinical characteristics of patients identified with confirmed or putative germ line JAK2 p.R564 variants. VAF is given for the p.R564 variant identified. For several of the patients, variants were confirmed as germ line via testing on cultured skin fibroblasts or family variant testing. Two patients had concurrent acquired mutation of p.V617F. The MPN-SAF TSS is provided when available as a measure of symptom burden. Family history is provided to the degree it was available upon review of the medical record. Family 1 consists of patients 1, 2, and 3.
↑, increased; CRVO, central retinal vein occlusion; CVA, cerebral vascular accident; DVT, deep vein thrombosis; F, female; het∗, heterozygous; HM, hematologic malignancy; LGL, large granular lymphocyte leukemia; M, male; NA, not available; NHL, non-Hodgkin lymphoma; PE, pulmonary embolism; Plts, platelets; PVT, portal vein thrombosis; R564X, R564L or R564Q; SVT, superficial vein thrombosis.