RESUMEN
BACKGROUND: Identification of blood group antigen frequencies in a population has various benefits in transfusion medicine. Most data in the literature include frequencies of these antigens in European and American countries. In this study for the first time we have reported frequencies of these antigens in the northeast of Iran. MATERIALS AND METHODS: Blood group antigens were characterized in the 522 blood donors in Mashhad, Iran. The following antigens including ABO, Rh (D, C, E, c, e), MNSs (M, N, S, s), Lutheran (Lu(a), Lu(b)), P (P, P(1)), Kell (K, k, Kp(a), Kp(b)), Lewis (Le(a), Le(b)), Duffy (Fy(a), Fy(b)) and Kidd (Jk(a), Jk(b)) were typed and phenotypes frequencies were expressed as a percentage. RESULTS: In the ABO blood group, the most common phenotype was O (33.9%) followed by A, B and AB. In the Rh blood group, the most common antigen was e (97.9%) and R(1)r (31.8%) being the most common phenotype. The most common phenotypes for MNSs, P, Lu and Kell blood group were M+N+, S-s+, P(1), Lu (a-b+), K-k+ and Kp (a-b+). A very rare phenotype of Lu (a-b-) was also observed in 2.7% of cases. We found rare phenotypes of Le (a+b+) and Fy (a-b-) in 7.9% and 3.4% of subjects, respectively. CONCLUSION: We determined some differences in phenotype frequencies of blood group compared with other studies. We found higher frequencies of B blood group and also more frequencies of some rare phenotypes, Lu (a-b-), Le (a+b+) and Fy (a-b-).