c.9253-6T>c REV3L: A novel marker of poor prognosis in Myelodysplastic syndrome.

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by dysplasias, ineffective hematopoiesis and risk of acute myeloid leukemia transformation. Approximately 90% of MDS patients present mutations in genes involved in various cell signaling pathways. Specialized DNA polymerases, such as POLN, POLI, POLK, POLQ, POLH, POLL and REV3L, insert a nucleotide opposite replication-blocking DNA lesions in an error-prone manner and, in this way, sometimes can actively promote the generation of mutation.

DNA repair gene expressions are related to bone marrow cellularity in myelodysplastic syndrome.

Objective: To evaluate the expression of genes related to nuclear excision (, and ), homologous recombination and non-homologous end-joining (, , and ) repair mechanisms, using quantitative PCR methodologies, and it relation with bone marrow cellularity in myelodysplastic syndrome (MDS).

Methods And Results: A total of 51 adult de novo patients with MDS (3 refractory anaemia (RA), 11 refractory anaemia with ringed sideroblasts (RARS), 28 refractory cytopenia with multilineage dysplasia (RCMD), 3 refractory anaemia with excess blasts type I (RAEB-I), 5 refractory anaemia with excess blasts type II (RAEB-II), and 1 chronic myelomonocytic leukaemia (CMML) were evaluated. For karyotype, 16.