Genetic analysis of driver mutations in classical myeloproliferative neoplasms – a study from a South Indian Tertiary Care Center

Background Despite being one of the most populated and diverse countries in the world, there is a paucity of data on the prevalence of driver mutations in classical myeloproliferative neoplasms (MPN) in India. Aim In the present study, we aimed to analyze somatic driver mutations such as JAK2 , CALR , and MPL in classical MPNs in a South Indian Tertiary Care Center. Patients and methods Out of 185 suspected MPN patients screened, based on WHO 2016 criteria, 72 MPN patients were included in this study. JAK2 V617F and MPL mutations were screened using an allele-specific PCR assay. JAK2 exon 12 and CALR exon 9 mutations were screened by PCR Sanger sequencing. Results In the present study, JAK2 V617F mutation was detected in 88.8% of polycythemia vera, 66.6% of essential thrombocythemia, and 53.3% of primary myelofibrosis (PMF) cases. CALR mutations were observed in 16.6% of essential thrombocythemia and 13.3% of PMF patients. In addition to the common type 2 mutation, we identified a rarely reported type 2-like mutation (c.1154_1155insATGTC) in a PMF patient. The identified mutations were mutually exclusive. We observed an absence of JAK2 exon 12 and MPL mutations in our study participants. Conclusion In the present study, we observed JAK2 and CALR mutations in 77.7 and 5.5%, respectively, in classical MPNs. We identified a rare CALR type 2-like mutation in a PMF patient, a first report from India.