Molecular biology of partial D phenotypes

• Published in: Transfusion clinique et biologique (Paris) Vol. 3; no. 6; pp. 511 - 516
• Main Authors: Avent, N.D., Finning, K.M., Liu, W., Scott, M.L.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Paris Elsevier SAS 1996; Elsevier
• Subjects: Biological and medical sciences; DNA - analysis; Exons; Fundamental and applied biological sciences. Psychology; Humans; Introns; Phenotype; Rh-Hr Blood-Group System - genetics; Sequence Analysis, DNA; Vertebrates: blood, hematopoietic organs, reticuloendothelial system; Blood group; Phenotype; Nucleotide sequence; Analysis; Rh-System; Molecular biology; Gene expression; Genome
• ISSN: 1246-7820
• DOI: 10.1016/S1246-7820(96)80073-5

We have examined all D VI variant phenotypes submitted to the workshop by a combination of RT-PCR, multiplex RHD PCR and immunoblotting with Rh antipeptide sera. Our findings suggest that all D VI phenotypes arise through hybrid RHD-RHCE-RHD genes. Genomic DNA derived from all D VI samples were shown to be RHD intron 4 negative when analysed with an RHD intron 4/exon 10 multiplex assay. We assume therefore that all D VI phenotypes involve gene conversion events involving at least exons 4 and 5 of the RHD gene. Analysis of a novel D and E variant phenotype individual (ISBT49) by RT-PCR has allowed the identification of a hybrid Rh gene composed of exons 1–4 RHD: 5 RHCE/D and 6–10 RHD. We propose that the partial D & E phenotype observed arises through D & E expression on the hybrid RHD-RHCE-RHD protein: as no transcripts encoding Rh E could be found.