TITLE:
Molecular Characterization of RHD in Rh-Negative Blood Donors in Congo Brazzaville
AUTHORS:
Ludmilhia Gudrid Fouti, Landry Fils Mpelle, Faust René Okamba Ondzia, Love Fresia Senda, Arsène Bikoue, Anicet Luc Magloire Boumba, Etienne Nguimbi
KEYWORDS:
Molecular Characterization, Rhesus, RHD Gene, Blood Donors
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.12 No.11,
November
18,
2024
ABSTRACT: Background: The D antigen is the most important and immunogenic antigen of the Rh blood group; its correct screening prevents any risk of alloimmunization in the RHD negative recipient. The D negative phenotype is characterized by the absence of the D antigen (RH1) on the surface of the erythrocyte. Three main mechanisms can generate this absence: total or partial deletion of the RHD gene, insertion of base pairs within the said gene and gene conversion. The objective of this study was to report the first data on RHD genotyping in RHD negative congolese blood donors. Materials and Methods: Blood samples came from regular RHD-negative blood donors selected from the blood transfusion stations in Brazzaville and Pointe-Noire. They were analyzed individually by conventional PCR, targeting exons 4, 5, 7 and 10 of the RHD gene. Results: Fifty-nine regular RHD negative blood donors were selected for this study. The immuno-hematological profile was determined individually, and the dccee phenotype was the most frequent (n = 52; 88.1%). The search for the weak D antigen was negative for all donors. Exons 4, 5, 7 and 10 of the RHD gene were amplified in the following respective proportions: 89.8%, 81.4%, 6.8% and 42.4%. Moreover, (1) donor was found to carry all four specific exons sought. Conclusion: Conventional PCR amplification allowed to study the presence of specific exons of the targeted D gene. At least one exon was detected in the entire study population. These results suggest that the RHD gene is indeed present in the donors studied and that the deletion cannot be considered as the main mechanism causing the RH-1 (D negative) phenotype in this sample.