STUDY OF SINGLE NUCLEOTIDE POLYMORPHISM IN DNMT3B GENE IN PATIENTS DIAGNOSED OF ACUTE LYMPHOBLASTIC LEUKEMIA

Acute lymphoblastic leukemia (CLL) is a cancer that damages bone and bone marrow and is characterized by an overproduction of lymphoblasts. These cells accumulate in the bone marrow and affect its ability to form normal cells, and can also be separated from the bone marrow and spread to all tissues in the body. It is the most common type of cancer in children, accounting for 35% of all cancers in children. Due to the fact that cancer belongs to the group of multifactorial diseases, both genetic and epigenetic variations, as well as environmental factors affect the origin and development of the disease. The cause of acute lymphoblastic leukemia is a type of epigenetic mechanism, the most studied in the process of DNA methylation, which occurs in the DNMT3B gene -579 G> T polymorphism. The study included control groups of 46 patients and 50 healthy individuals diagnosed with acute lymphoblastic leukemia. DNA was extracted by Salting-out method from blood samples taken in EDTA tubes, polymorphism in genotypes was investigated by PCR-RFLP methods, and the results were evaluated by gel electrophoresis. Analysis of the results showed that the genotype frequencies in the patient groups were 30.43% of normal homozygous GG, 54.35% of heterozygous GT, 15.22% of mutant homozygous TT, while in control groups this ratio was normal homozygous GG 34%, heterozygous GT 50%, mutant homozygous TT was defined as 16%. When the groups were analyzed in terms of allele frequency, the frequency of G allele was 62.1% in the patient group and 59% in the control group. Mutant T allele was detected in 37.9% of patients and 41% of healthy people. Based on the analysis of the results, no statistically significant correlation was found between the mutant T allele and the risk of acute lymphoblastic leukemia. (OR = 1.06; 95% CI = 0.60-1.88; P = 0.845). However, the presence of a high risk factor for TT genotype was identified in groups of patients under 25 years of age.