High prevalence of the germline JAK2 46/1 haplotype and V617-mutationin Swedish patients with Budd-Chiari syndrome and Portal Vein Thrombosis

• Background & Aims: To determine the prevalence of the somatic JAK2 V617F mutation and distribution of the germline JAK2 46/1 haplotype in Budd-Chiari Syndrome (BCS) and portal vein thrombosis (PVT). Methods: Real-time PCR was performed to genotype for the JAK2V 617F mutation and the 46/1 haplotype (tag-SNPs rs12343867, T>C and rs12340895, C>G) in blood samples of 19 BCS and 91 PVT patients (without intra-abdominal malignancy), and 283 controls from a background population. Results: The prevalence of JAK2 V617F-mutation was 63% in BCS and 14% in PVT patients. 10% in BCS and 2% in PVT had V617F negative MPD. Conversely, V617F positive subjects without known MPD was found in 5% of the BCS and in 1% of PVT patients. The frequency of the JAK2 46/1 haplotype was significantly higher in BCS (53%) and PVT (36%) patients compared to controls (27%) (p=0.02; OR=3.0; 95% CI 1.5-5.9 and OR=1.51; 95% CI 1.1-2.1, respectively). In PVT patients the JAK2 haplotype was highly enriched in non-cirrhotic patients (41%) (p <0.01 ; OR=1.8; 95% CI 1.2-2.6) but not in cirrhotic patients (23%) (p=0.53 ; OR= 0.8; 95% CI 0.4-1.7). An increased JAK2 46/1 haplotype frequency was evident only in V617F mutation positive patients. Conclusions: The prevalence of JAK2 V617F was high in BCS (63%) and non-cirrhotic PVT (14%), facilitating detection of latent MPD. A negative result dose not rule out MPD. The occurrence of the JAK2 46/1 haplotype was significantly higher in V617F mutation positive patients but not in mutation negative patients, suggesting that the haplotype may not have an independent role separated from the V617F mutation in BCS and PVT patients.

Nyckelord

Budd-Chiari syndrome; Portal vein thrombosis; Myeloproliferative disorders; JAK2 V617F mutation; JAK2 46/1 haplotype; Thrombophilia; Liver cirrhosis

MEDICINE

MEDICIN

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)