This article continues a series of works estimating carrier frequencies of mutations associated with the development of common monogenic disorders in the Russian population. The study aimed to establish the frequency of GJB2 and GALT mutations in first-time blood donors. Genotyping of 1000 first-time blood donors who identify themselves as Russians and permanently reside in the Russian Federation detected 37 carriers of GJB2 mutations associated with sensorineural hearing loss (carrier frequency in the sample was 3.7 %, or 1 : 27) and 6 carriers of GALT mutations associated with galactosemia (carrier frequency in the sample was 0.6 %, or 1 : 167). In one carrier, concurrent mutations were detected; thus, in total 42 carriers of GJB2 and GALT mutations were detected (carrier frequency in the sample was 4.2 %, or 1 : 24).