Janus kinase (JAK) 2 V617F mutation in Asian Indians with cerebral venous thrombosis and without overt myeloproliferative disorders.

It is unclear whether the somatic JAK2V617F mutation, a marker for chronic myeloproliferative disorders (MPDs), is associated with cerebral venous thrombosis (CVT) in the absence of MPD. Our aim was to determine the prevalence and association of the JAK2V617F mutation among patients with CVT and without overt MPD. We investigated 372 CVT patients without features suggestive of MPD and 383 age- and gender-matched healthy controls, for the JAK2V617F mutation. Genotyping was done by polymerase chain reaction and restriction fragment length polymorphism. The heterozygous JAK2V617F mutation was present in 22 of 372 patients (5.9%) and 2 of 383 controls (0.5%). Logistic regression analysis showed this mutation to be an independent predictor of CVT after adjusting for the conventional risk factors (adjusted odds ratio: 5.47, 95% CI: 1.06-28.27, p=0.04). The mutation was more prevalent in men (p=0.005). Patients with JAK2V617F mutation were older (p=0.036), and had higher mean hemoglobin level (p<0.0001) than those without the mutation. Smokers with the mutation had 9.45-fold increased risk of CVT compared to non-smokers without the mutation (OR: 9.45, 95% CI: 1.17-76.02, p<0.0001). We conclude that the JAK2V617F mutation could contribute to increased risk of CVT in Indians. Larger studies in other ethnic populations are warranted before considering the inclusion of the JAK2V617F gene polymorphism into the routine diagnostic workup of CVT.