Frequency of L1721W Polymorphism in TET2 Gene Among a Cohort of Sudanese Patients with Myeloproliferative Disorders: Possible Roles in Pathogenicity and Leukemic Transformation
International Journal of Genetics and Genomics
Volume 5, Issue 5, October 2017, Pages: 49-53
Received: Feb. 27, 2017; Accepted: Apr. 21, 2017; Published: Oct. 18, 2017
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Anas Abdelrahman Ibrahim, Department of Hematology & Immunohematology, Faculty of Medical Laboratory Sciences, Omdurman Islamic University, Khartoum, Sudan
Eltahir Awad Gasim Khalil, Department of Clinical Pathology & Immunology, Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan
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Transformation of myeloproliferative disorders (MPDs) to acute leukemia is an evitable event that represents a stumbling block in the management of patients. The Janus Kinase-2 JAK2V617F mutation of MDP does not clarify the phenotypic variability observed in this disorder. But, a mutations in Ten-eleven-translocation-2 (TET2), a putative tumor suppressor gene, was recently implicated in MPDs and other hematologic malignancies. TET-2 is believed to play a role in leukemic transformation. This study aimed to determine the frequency of L1721W polymorphism in TET2 gene in a cohort of Sudanese patients with MPDs. Following informed consent, 25 (25/50, 50%) patients with polycythemia rubra vera (PRV), thirteen patients (13/50, 26%) with essential thrombocythemia (ET), eleven patients (11/50, 22%) with chronic myeloid leukemia (CML), and one patient (1/50, 2%) with primary myelofibrosis (PMF) were enrolled. None of the patients was in the transformation phase. Patients were diagnosed based on clinical picture, hematological parameters and JAK2V617F and BCR_ABL molecular aberrations. JAK2V617F was detected in Ph-negative-MPDs cases as (24/25, 96%) in PRV, (10/13, 76%) in ET, and (1/1, 100%) in PMF. BCR_ABL fusion was detected in all (11/11, 100%) cases of CML. DNA was extracted using the guanidine chloride method, followed by (PCR-RFLP) analysis. Only one patient showed the presence of L1721W polymorphism of the TET2. It was inferred that the low frequency of this transformation within the study cohort [all in chronic phase] probably indicates that it plays a minor role in MPD pathogenesis, while its role in blast transformation needs further studies in MPD patients.
Myeloproliferative Disorders, L1721W Polymorphism in TET2 Gene, Sudanese Patients
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Anas Abdelrahman Ibrahim, Eltahir Awad Gasim Khalil, Frequency of L1721W Polymorphism in TET2 Gene Among a Cohort of Sudanese Patients with Myeloproliferative Disorders: Possible Roles in Pathogenicity and Leukemic Transformation, International Journal of Genetics and Genomics. Vol. 5, No. 5, 2017, pp. 49-53. doi: 10.11648/j.ijgg.20170505.11
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