New germline mutations in PTEN and RAD51D genes among the Buryat Mongol breast cancer patients

Polina Gervas¹, Aleksey Molokov², Nadezda Cherdyntseva^3
1Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia, pgervas@yandex.ru
²Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia, amolokov@inbox.ru
³Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia, nvch@tnimc.ru

Breast cancer is the most prevalent female malignancy worldwide. In recent decades, breast cancer has been the most common malignancy in the regions of Siberia and Russian Far East, which occupy about 70% of the Russian Federation. The population is descended primarily from newcomers (Slavic ancestors) and indigenous population (Mongolian). More than 13.8 million women inhabit these regions. Currently, little information has been reported regarding the molecular factors associated with increased risk of developing hereditary breast cancer in the indigenous population (Buryats, Evenks, Altaians, Tuvinians, Khakassians). For the indigenous population, there are no standards for the treatment of inherited breast cancer. Breast cancer prevention models for indigenous population have not been developed yet. For \”slavic\” patients with a family history, the BRCA1/2 mutation testing is the standard of care. In addition, the development of new antitumour drugs has resulted in improved survival rates. More than 1000 mutations of the BRCA1 gene have been identified. Recent research is focused on the confirmation the beneficial effect of identified mutations. In our previous study we did not find \”slavic\” mutations of the BRCA1 gene in Mongoloid breast cancer patients having family history. Pathological mutations in the BRCA1 gene among indigenous people have not been identified using Sanger sequencing (RFBR grant 12-04-90830). Thus, the advances in molecular oncology for the treatment of hereditary breast cancer are not available for the indigenous population of the Siberian and Far Eastern region.