The spectrum of genetic variants of the a- and b-globin clusters in patients with hemoglobinopathies living in the Republic of Dagestan

Hemoglobinopathies are a group of hereditary hemolytic anemias common in the countries of the Mediterranean, Southeast Asia and Africa, where malaria was previously common. Due to population migration and an increase in the number of mixed marriages, hemoglobinopathies are also relevant to Russia. Among the Russian Federation's subjects, the Republic of Dagestan is the most endemic region for the incidence of hemoglobinopathies. This study aimed to identify the spectrum of mutations in patients with hemoglobinopathies living in the Republic of Dagestan. The research was approved by Independent ethic committee and the academic board of Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology (Moscow, Russia). Material from 100 patients was sent for molecular genetic research to the Laboratory of Molecular Biology, Federal State Budget Scientific Institution Scientific Research Center for Surgery named after Dmitry Rogachev. Genetic variants of the genes of the a- and b-globin clusters were determined using multiplex ligase-dependent amplification of samples and Sequencing by the Sanger method. Eighteen genetic variants with different frequencies were detected. The mutation frequency of the b-globin cluster was 62.5%, the a-globin cluster was 23.2%, and the variants leading to the appearance of abnormal hemoglobin were 14.3%. The five most common genetic variants among this cohort were also identified: CD8(-AA) and IVSI-110 (G>A), -(a) 3.7 and -(a) 20.5 and the CD6 variant GAG>GTG [Glu>Val] leading to abnormal hemoglobin S.