Poluben L. "Molecular Genetic Features of Ph-negative Myeloproliferative Neoplasms in patients exposed to ionizing radiation due to Chernobyl nuclear accident".

The dissertation is devoted to the study of the molecular genetic features of chronic Ph-negative myeloproliferative neoplasms (MPN) in patients exposed to ionizing radiation (IR) due to the Chernobyl nuclear accident. JAK2, MPL and CALR gene mutations were detected using real-time PCR and Sanger sequencing. It was found that more cases negative for the usual mutations of the driver genes (JAK2, MPL and CALR), lower rate of JAK2 V617F and higher rate of CALR 1-like type mutation were among IR-exposed MPN patients in comparison to unexposed MPN patients. It was shown that JAK2 mutations were associated with a higher erythrocyte count, hemoglobin and hematocrit levels, and CALR gene mutations were associated with a higher platelet count. Additional sequence variants and genomic alterations were examined in IR-exposed and unexposed MPN by whole exome and targeted sequencing, and high-density oligo-SNP microarray platform. A wide spectrum of genomic alterations was identified in IR-exposed and unexposed MPN patients, positive for one of usual mutations of driver genes or negative for them. IR-exposed and unexposed MPN patients did not differ regarding frequencies of genomic imbalances types. Significant number of variants were detected in genes which were common for IR-exposed and unexposed MPN patients, however several alterations were identified exclusively to IR-exposed MPN patients negative for usual mutations of driver genes. Among these variants, EZH2 D659G at 7q36.1 and SUZ12 V71M at 17q11.2 with copy number losses and ATM S1691R at 11q22. 3 with copy-neutral loss of heterozygosity that might be involved in MPN development. There were identified sequence variants which might predispose the MPN development and be related to the IR exposure. Obtained data indicate the contribution of impaired DNA transcription and epigenetic regulation to MPN development in IR-exposed subset of patients in addition to the canonical pathway. On the basis of the results we designed a targeted sequencing panel including 309 MPN-related genes, proposed a list of genes for integration in the current diagnostic criteria of MPN, negative for JAK2, MPL and CALR gene mutations, in Ukraine, and recommended a list of genes for the first priority detection in IR-exposed MPN patients, negative for JAK2, MPL and CALR gene mutations.