Molecular analysis of the GYPB gene to infer S, s, and U phenotypes in an admixed population of Minas Gerais, Brazil

objective: to implement genotyping for s, s and u antigens of the mns blood group system at the funda？？o hemominas and to evaluate the occurrence of gypb gene polymorphisms associated with the u- and u+var phenotypes and deletion of the gypb gene for the first time in an admixed population of minas gerais, brazil. the s, s and u antigens can cause transfusion reactions and perinatal hemolytic disease. genotyping is a useful tool in immunohematology, especially when phenotyping cannot be performed. methods: ninety-six samples from blood donors and patients with sickle cell disease previously phenotyped for the s, s and u antigens were selected. allele-specific primer polymerase chain reaction (asp-pcr) and polymerase chain reaction -restriction fragment length polymorphism (pcr-rflp) assays were employed to identify the gypb*s and gypb*s alleles and the gypb(p2) and gypb(ny) variants, as well as deletion of the gypb gene. results: the results of allele-specific genotyping (gypb*s and gypb*s) were totally in agreement with the phenotyping of s+ (n = 56), s+ (n = 60) and s- (n = 35) samples. however, the gypb*s allele, in association with the gypb(p2) variant, was detected in 17.5% of the s- samples (n = 40), which shows the importance of assessing this variant in the brazilian population. of the s-s- samples (n = 10), 60% had the deletion of the gypb gene and 40% were homozygous or hemizygous for the gypb(p2) variant. conclusion: genotyping was an effective strategy to infer the s, s, and u phenotypes in the admixed population from minas gerais (brazil) and may contribute to transfusion safety.