Calreticulin mutational analysis in patients with myelofibrosis

Abstract

Objective Our study aimed to determine the occurrence of CALR and JAK-2 mutation in patients with myelofibrosis. Patients and methods This cross-sectional study was conducted in the Department of Hematology, Lady Reading Hospital, Peshawar, and Princess Nourah Bint AbdulRehman University, Saudi Arabia. Blood samples and data were collected from patients in the Hematology Department of Lady Reading Hospital, Peshawar, Pakistan. Nonprobability convenience sampling technique was used. All patients of JAK-2 V617F-positive and JAK-2 V617F-negative primary or secondary myelofibrosis due to polycythemia vera or essential thrombocythemia were included. After taking blood and bone marrow sampling, DNA extraction was done manually, and these samples were analyzed for CALR mutations by Sanger sequencing technique. Data were recorded and analyzed in SPSS, version 20. Results Of 118 patients of myelofibrosis, we have found two types of genetic variations. One is single nucleotide polymorphism (SNP) in the 3’ UTR variant and the other is a novel indel frameshift mutation in the form of p.Leu 367 Thr Fx 63. Among these 118 patients, 14.40% patients had the indel frameshift mutation, whereas 46.61% patients had SNPs. The remaining patients did not harbor any significant changes. Conclusion Our study concluded that most patients had a SNP in the 3’ UTR variant and a novel frameshift mutation. Further large-scale studies should be organized to determine the co-occurrence of calreticulin mutations in the JAK-2-positive patients of myelofibrosis. The influence of this coexistence on the phenotype and clinical course of myelofibrosis should also be studied to better understand the diagnosis and prognosis of the patients with myelofibrosis.