Abstract
Background and Objectives
Detection of weak D blood type can lead to the saving of RhD negative blood components and can reduce RhIG consumption. Therefore, determining the frequency of weak D alleles in our country is necessary.
 
Materials and Methods
In this descriptive study, a total of 105 blood samples with weak expression of D antigen from 21 provinces among Iranian blood donors were studied. The phenotype of samples was tested for Rh D, C, c, E and e antigens by routine serological methods. Weak D variants were evaluated by PCR-SSP, RFLP and DNA sequencing methods.
 
Results
Among 105 weak D samples, 9 weak D alleles and 2 partial D alleles were found. The most prevalent weak D type in our population was weak D type 15(38.1%), weak D Type 1(10.48%), Type 5(7.62%), Type 4 (4.76%), Type 80 (3.8%), Type 3 (1.9%) and Type 11 , Type 8 , Type 100 each (0.95%) and Partial D DLO (8.57%), and partial D V a /DAU (0.95%). We also observed the correlation between weak D type 15 and E antigen and weak D type 1 and Partial D DLO and C antigen.
 
Conclusions 
There is a significant difference between the prevalence of Weak D variants among our blood donors compared to European and American white populations with a high incidence of weak D 1, 2 and 3, equally compared to African population with a high incidence of Partial D and weak D type 4, as well as Asian population with a high prevalence of Del.