Genetic variability of blood groups in southern Brazil.

We evaluated genetic variability among the blood groups Kell (c.578C> T and c. t790T> C), Kidd (c.838A> G), Duffy (c.125A > G, c.265C > T and c.1-67T> C), Diego (c.2561C > 7), MNS (c.143T > C) and Rh (c.676G > C) in Rio Grande do Sul in southern Brazil. Genetic profiling from 382 volunteer blood donors was performed through allelic discrimination assays using a hydrolysis probe (TaqMane) with a real-time PCR system. The sample was divided into two groups: Euro-Brazilian and Afro-Brazilian. A comparison with studies from other regions of Brazil and the 1000 Genomes Database showed significant differences for almost all polymorphisms evaluated in our population. Population differentiation between the Euro- and Afro-Brazilian groups was low (F-sT value 0.055). However, when each locus was evaluated individually, KEL*06 and Fr*02N.01 allele frequencies were significantly higher in the Afro-Brazilian group than in the Euro-Brazilian group. Ethnic classification that uses phenotypic criteria to find blood units with rare antigens may be important when there is a need to detect blood units with an absence of Duffy antigens. There is also a greater probability of finding donors in the Afro-Brazilian group. Taken together, the data indicate strong European and African contributions to the gene pool, with intense admixture.