CC BY-NC-ND 4.0 · Indian J Med Paediatr Oncol 2019; 40(01): 141-143
DOI: 10.4103/ijmpo.ijmpo_221_17
Case Report

A novel in-frame 231bp deletion mutation in ABL1 kinase activation loop

Prashant Ajit Deshpande
Department of Hematopathology, Marathwada Medical and Research Institute Kamalnayan Bajaj Hospital, Aurangabad, Maharashtra, India
,
Gajanan Bhanudas Padmawar
Department of Cytogenetics, Marathwada Medical and Research Institute Kamalnayan Bajaj Hospital, Aurangabad, Maharashtra, India
,
Venkatesh S Ekbote
Department of Clinical Hematology, Marathwada Medical and Research Institute Kamalnayan Bajaj Hospital, Aurangabad, Maharashtra, India
› Author Affiliations
Financial support and sponsorship Nil.

Abstract

Tyrosine kinase domain (TKD) mutation is one of the most common causes for tyrosine kinase inhibitors' resistance in patients with chronic myeloid leukemia (CML). Mutations in the exon 7 of ABL1 gene are one of the most common TKD mutations, especially in the Indian population, but they are frequently underreported, and their clinical significance is not clear. We are reporting a novel ABL1 exon 7 mutation in a previously diagnosed and treated patient CML who presented at the blast crisis stage. Cytogenetic studies showed multiple copies of Philadelphia (Ph) chromosome along with isochromosome 17. Kinase domain mutation studies showed a novel 231bp in-frame deletion mutation (p. 372_448del) in the activation loop of BCR-ABL1 chimeric protein. The given mutation would result in a complete loss of activation loop, including DFG domain-regulating activation status of the catalytic domain. This mutation, along with cytogenetic abnormalities, could have contributed to progression to blast crisis.



Publication History

Article published online:
08 June 2021

© 2019. Indian Society of Medical and Paediatric Oncology. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).

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