Background: Transfusion support for patients with irregular antibodies to red blood cell (RBC) antigens of high frequency may be hampered by lack of appropriate antigen-negative RBC units. Often, this perceived lack is due to the low number of typed donors. We developed a simple multiplex polymerase chain reaction (PCR) method to screen for donors with rare blood group phenotypes.
Study design and methods: A multiplex PCR with sequence-specific priming predicting Yt(a), Co(a), Lu(b), and Kp(b) antigens was developed based on a commercially available system (Extract-N-Amp, Sigma-Aldrich) that obviates the DNA purification step. PCR amplicons were analyzed by size fractionation in a 2 percent agarose gel. Samples representing rare phenotypes were identified by the lack of one of the four visible bands. Donors of blood phenotype O D- ccddee were screened.
Results: Excluding the preparation of the reaction mixture and the gel, the whole procedure consisted of five pipetting steps. Hands-on time was 102 minutes for 91 donors. After optimization, interpretable results were obtained in 85 percent of samples without repetition. Among 3422 donors tested, 1 Kp(b-), 6 Co(a-), 10 Yt(a-), and 5 Lu(b-) donors were detected.
Conclusions: Multiplex PCR is a simple, versatile, and cost-efficient method for the screening for donors with rare phenotypes who may be identified by their genotype. If such donor screening is introduced on a broad basis, transfusion support for patients with anti-Co(a), anti-Yt(a), or anti-Lu(b) will be considerably improved.