Molecular bases of unexpressed RHD alleles in Chinese D− persons

BACKGROUND: The aim of this study was to use a systematic survey to analyze RHD alleles in Chinese D− donors who do not express D antigen or who lack functional RhD protein. STUDY DESIGN AND METHODS: A total of 733 D− Chinese donors, not including Del phenotypes, were investigated by RHD polymorphism–specific polymerase chain reaction (PCR), Rhesus box PCR-PstI digestion, and RHD sequencing. The frequencies of identified alleles were calculated. RESULTS: Three genetic mechanisms and eight alleles were found associated with the Chinese D− phenotype. One new RHD/CE hybrid allele and one novel mutation were also found. The rates of total deletion and the most frequent hybrid allele RHD(1)-CE(2-9)-D(10) were similar to those found in previous studies. A previously reported mutation RHD(711delC) was found to be the predominant cause of aberrant RHD alleles. CONCLUSION: Informative population-based data for improving molecular diagnostic strategies for Chinese D− persons are suggested by this study. This type of systematic knowledge is important for the development of typing and transfusion strategies for the Chinese population.