Abstract
Background and Objectives
Hemagglutination has limitations in identifying the phenotype of patients who have been recently transfused due to the presence of donor red cells (RBCs) in the patient’s circulation. Kidd blood group is one of the most important blood groups in transfusion medicine and related antibodies are responsible for one third of delayed haemolytic transfusion reactions (DHTRs). In this study we developed a molecular procedure for detection of alleles responsible for Kidd blood group in thalassemia patients.
 
Materials and Methods
In this cross sectional descriptive study, one hundred of alloimmunized thalassemic patients from Tehran Adult Thalassemic Clinic in 2017 were studied. The phenotype of samples was tested by routine serological methods. PCR-SSP, PCR-RFLP and DNA sequencing were used to determine the genotype of kidd blood group for these patients.
 
Results
Discrepancies were found between the phenotype and genotype in 20 out of 100 cases. In 11(55%) cases phenotype was determined as Jk (a⁺b⁺) but genotype was JKA/JKA, in 7 (35%) cases phenotype was Jk (a⁺b⁺) while the genotype showed JKB/JKB, 1(5%) case had been phenotyped as Jk (a⁺b^-) but it was genotyped as JKA/JKB, and 1(5%) case had been phenotyped as Jk (a^-b⁺) but it was genotyped as JKA/JKB.
 
Conclusions 
Molecular techniques as a complementary method together with the results of serological methods can help resolve the problems caused by blood transfusion and bring about accurate determination of phenotype in thalassemic patients with multiple blood transfusions.