Bioinformatics approach to the relationship between immunoglobulin gene variant subtypes, subclones, mutations and disease biology in chronic lymphocytic leukemia - small lymphocytic lymphoma (CLL/SLL)

Chronic Lymphocytic Leukemia (CLL) and Small Lymphocytic lymphoma is the most common adult leukemia in western countries, with an incidence of up to 30%. CLL is a highly heterogeneous disease clinically. For this reason, some CLL patients live for many years without treatment, while others succumb to the disease despite treatment. Antigen stimulation, SHM status in IGHV genes, changes in the microenvironment of B lymphocytes, genetic mutations and epigenetic factors are thought to play a role in this heterogeneity seen in CLL. Many studies around the world are carried out on B lymphocyte clones, which have a strong relationship with antigen stimulation from these factors and are called "Stereotypic Subset". These studies are important in terms of understanding the heterogeneity of CLL and the predictive and prognostic properties of subsets. In this thesis, 112 patients diagnosed with Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma in the Pathology Department of AUTF between 2006-2021 were examined for somatic hypermutation of the IGHV gene region with the New Generation Sequence technology. Subsets associated with patients were compared with del(11q), del(17p), trisomy 12 and del(13q) cytogenetic anomalies, especially in IGHV databases. We found that most of the findings in our study were similar to the literature. The difference in some data may be associated with the different geographic and ethnic origins of the patients. In this study, the distribution of IGHV genes, somatic hypermutation status, determination of subsets and their association with cytogenetic anomalies in a group of CLL/SLL patients in the geography of Turkey were revealed. In order to better understand CLL disease in our country, the increase of such studies and their comparison with international databases are of high importance.