Identification of Altered RHD and RHCE Alleles: A Comparison of Manual and Automated Molecular Methods.

RH genotyping is particularly useful in clinical transfusion practice to discriminate partial D from weak D, distinguish alloantibodies from autoantibodies, detect the absence of high-prevalence Rh antigens, and to screen for Rh-compatible donors. Because of the complexity of the RH locus, many areas of RHD and RHCE must be sampled for accurate genotyping; gene sequencing is often required. Manual assays are labor-intensive and complex interpretation is required. Automation is needed to expedite testing and to make a DNA-based approach more accessible for application to clinical transfusion practice. We determined the performance of the automated RHD and RHCE BeadChip⠪ for detecting RHCE and RHD polymorphisms by testing 149 samples referred for RHD analysis and 168 referred for RHCE genotyping. The majority were assayed in parallel to determine concordance of the BeadChip⠪ assays with manual polymerase chain reaction-restriction fragment-length polymorphism and gene sequencing. RHD alleles were concordant between manual and automated methods with the exception of seven alleles. For RHCE, all were concordant with the exception of six alleles. This study is significant for the number of samples analyzed by both manual and automated methods. All samples were problem referrals encountered in routine transfusion practice. [ABSTRACT FROM AUTHOR]