Aims/Objectives:We aimed to analyse the molecular backgrounds and red blood cell (RBC) antigen expression of a male blood donor with Rh mod phenotype and his family members.Background: Rh deficiency phenotypes are rarely found worldwide and are characterised by the lack of Rh antigen expression on RBCs. During routine screening, we found a blood donor who seemingly lacked Rh antigens. Therefore, we recruited the donor and his family for further investigation. Methods:RBC serotyping and antibody screening/identification were performed for each sample. A routine blood examination was also conducted. RHD, RHCE and RHAG were sequenced at the genomic DNA or RNA level. Eleven antigens or proteins associated with Rh complex were tested using flow cytometry analysis. Results:The proband and one of his brothers showed extremely weak D antigen and Rh expression levels but did not manifest anaemia. Most of the expressed RBC antigens of the two Rh-deficient individuals were similar to the previously reported cases but with some exceptions. Molecular analyses demonstrated homozygous expression of a novel RHAG allele, namely, c.[572G>A;707A>C], both in the proband and one of his brothers. Conclusions:To our knowledge, we identified the second double-variant RHAG allele and the first one related to Rh mod phenotype. The novel allele was also confirmed to be heritable by family analyses.

Objectives:We aimed to analyse the molecular backgrounds of the family in which an eight-day-old baby was confirmed to have hemolytic disease of the newborn (HDN) and phenotype observed for the baby did not conform to the expected phenotype. Background:The silent RHCE allele is rare in the Rh system. Methods:To determine the antibody specificity, her family members' blood samples were collected and tested using routine serological methods. The Rh C + c-e + E-phenotype observed for the baby did not conform to the expected phenotype based on the maternal RhC-c + E + e-phenotype. The RH genes of the family members were further analysed by sequencing. Results:The Rh phenotypes of the baby, her brother, her mother and father were CCDee, CcDEe, ccDEE and CCDee, respectively. IgG anti-e was confirmed to cause the HDN in the case. A heterozygous silent RHCE * 03(c.1059G > A) mutation in exon 7 was found in the baby and her mother, which is a novel nonsense allele caused by a premature termination codon (Trp353stop). Conclusion:The silent RHCE * 03(c.1059G > A) variant was observed in a heterozygous state in mother and baby. We predict that, had this occurred in the homozygous state, it would give rise to the rare D--phenotype. To enhance the safety of transfusion, considerable attention should be paid to the RHCE gene in the Chinese population.