ABSTRACT Introduction:

To date, 340 antigen-organized 43 blood group systems are recognized, being ABO, Rh, Kell, Duffy, Kidd, MNS and Diego the most clinically relevant. The aim of this study was to assess the distribution of alleles and genotypes of the blood group systems Rh, Kell, Duffy, Kidd, MNS and Diego in 810 blood donors registered in the hemotherapy unit in northwest Rio Grande do Sul, Brazil Methods: We evaluated the genetic variability of blood groups Rh (c.676G>C and c.307C>T), Kell (c.578C>T), Kidd (c.838A>G), Duffy (c.125A>G and c.l-67T>C), Diego (c.2561C>T) and MNS (c.143T>C) in 810 volunteer blood donors of Rio Grande do Sul, southern Brazil. The genetic profiling was performed through allelic discrimination assays using hydrolysis probes (TaqMan®) real-time PCR system.

Results:

The most frequent blood group genotypes found in our study population were: RHC*Cc (51.5%), RHC*ee (70.1%), FY*A/FY*B (49.3%), GATA -67T/T (93.5%), KEL*2/KEL*2 (93.4%), Jk*A/JK*B (53.2%) and DI*02/DI*02 (95.4%). Some statistical differences were observed on comparing the population of this study with populations from other states in Brazil, mainly with population of Minas Gerais, Bahia and Paraná, which showed some differences from the population of Porto Alegre, which was more similar to those of Santa Catarina and São Paulo Conclusion: The frequency of red blood cell polymorphisms in our study is different from that of blood donors in other regions of Brazil. The results showed the importance of extended genotyping in adequate blood screening and the existence of rare genotypes in Brazilian regular blood donors