Molecular Mechanism of Anti-e Like Antibodies in RhDCCee Phenotypic Individuals

The aim was to investigate the serotype characteristics and molecular mechanism of anti-e like antibody production in individuals with RhDCCee phenotype from a patient with PTR.

ABO, RhD, and RhCcEe blood groups were identified by micro-column gel card, the irregular antibody screening and antibody specificity were identified by anti-human globulin assay. RHD and RHCE genes were typed by PCR-SSP, RHD/RHCE sequences were analyzed by first generation and third generation full-length sequencing.

ABO and Rh phenotypes were type O and RhDCCee. The irregular antibodies were positive and specific antibodies were anti-e. PCR results showed that RHD exons 1 - 10 were all positive, while RHCE exons 1, 3 - 10 were positive, exon 2 was negative. The first-generation sequencing of RHD/RHCE showed that RHD exons 1 - 10 were without mutations, RHCE exons 1 and 2 had common point mutations, no novel mutation point was found in exons 3 - 10. The full-length sequencing of RHD/RHCE showed that the new allele of RHD*01 could not be con-firmed, and a sequencing depth decrease was found in exon 3 region. The RHCE two haploids were all Ce and the alleles were RHCE*02 or RHCE*Ce. The mutation site of RHCE exons were the same as that of the first-generation sequencing; however, the three generations of full-length sequencing showed that the RHCE exon 2 and 3 were very low in sequencing depth and there might be structural variation.

The molecular mechanism of anti-e like antibodies in RhDCCee phenotype individuals is not completely clear. Three generation full-length sequencing indicated that this phenomenon may be caused by structural variation of RHD/RHCE genomic.