investigating the frequency of anti-a1 antibody in individuals with a2 blood group

background & aims: mistyping either a donor or a recipient can lead to transfusion with abo incompatible blood which results in severe intravascular hemolysis and may even result in the death of the recipient. abo phenotype is one of the essential tests in immunohematology. eighty percent of blood group a and ab persons are subtype a1 and a1b, respectively. the other 20% of these blood groups are subtype “non-a1,” most often a2 (or a2b). a1 phenotyping is not routinely performed in compatibility testing however, some patients and donors may be identified as “a, non-a1” or “ab, non-a1b” in the course of routine blood bank typing because they have anti-a1 antibody in their plasma. anti-a1 is a cold antibody with no clinical significance, but if reacted at 37˚c it can be clinically significant, that happens rarely. at the present, we report the prevalence of blood groups that have anti-a1 antibody and have clinical significance. the study was done to assess the prevalence of a subgroup and the transfusion implications.     materials & methods: an analysis was performed on patients during the period from june 2014 to november 2014. in this descriptive study, we enrolled 245 samples using random sampling method. to confirm the prevalence of a1 and a2 subtypes in abo grouping, we conducted a few tests. the collected data were analyzed by spss 15 statistical software.     results: there was about 94.6% of a1 subgroup and 5.4% of cases were of a2 subgroups. there was no proportion and prevalence of a1-antibody in a2 blood group in our samples, because there was no reaction between the blood serum of patients with cell a1 references. there was no trace of anti-a1 in the plasma of patients.     conclusion: the collected data show that implementation of some subgroups such as a1 and a2 and anti-a1 in blood grouping is vital for abo blood typing       source: urmia med j 2015: 26(6): 481 issn: 1027-3727