Genetic defects in patients with primary immunodeficiencies in the Republic of Belarus

Primary immunodeficiency diseases (PID) are a heterogeneous group of genetically determined diseases of the immune system. Patients with a PID are characterized by increased infectious sensitivity, a high rate of development of autoimmune diseases and malignant diseases. All these factors lead to a high incidence of early child mortality. We identified 191 patients (120 males and 71 female) with genetically confirmed PID, which are represented by 25 nosologies. We found 32 variants that have not been previously described. Most of these variants were small deletions (n = 13) that lead to the synthesis of a shortened protein. Missense variants rank second in frequency (n = 11). Missense mutations lead to changes in the amino acid sequence of the protein. These mutations affect the structure of a protein and change the functional activity of a protein.