Fig. 3

Algorithm to resolve a serologic RhD-negative phenotype by red cell genotyping for DEL. All individuals in the 3 clinical cohorts (see Fig. 1) can be tested for the presence of the RHD gene and the Asian type DEL. Typically, rapid screening, such as PCR-SSP assays, can resolve the Rh type. Only in rare cases, nucleotide sequencing will be required, if resolving other complete DEL and partial DEL is desired