Association of altered E RHCE*cE(697G,712G,733G,744C) with altered D RHD*46C

OCHOA G; NOGUES N; MUÑIZ DIAZ E; TARRAGO M; GOLDMAN M; VEGE S; WESTHOFF C; VIETZ C; LUJÁN M; TRUCCO BOGGIONE C; COTORRUELO C

Cancún

Congreso; 32nd International congress of the International Society of Blood Transfusion; 2012

International Society of Blood Transfusion

Background The uncommon RHCE*cE(697G,712G,733G,744C) allele encodes an altered form of E antigen associated with RBC serologic E typing discrepancies (1). RHD*46C>T encodes a Trp16Arg change and RBCs have very weak or undetectable D antigen (2,3). A number of RHD and RHCE genetic variants have been found in association (in cis). Examples include RHD*DAR with RHCE*ceAR, and RHD*DIVa with RHCE*ceTI. Here we investigate the RHCE alleles in samples with variant RHD*46C, including the index cases (2,3). Materials & Methods Standard direct or indirect agglutination techniques in tube or gel and standard adsorption-elution techniques were used for serological tests. Antibody reagents and reactivity of the RBCs are listed. For molecular tests, we performed standard DNA sequencing, cDNA sequencing, PCR-RFLP, Rhesus box analysis, or allele-specific hybridization on an oligonucleotide microarray (BloodChip, Progenika). Results expressed in attached table. Conclusions In six unrelated and geographically disparate samples with variant RHD*46C, three had variant RHCE*cE(697G,712G,733G,744C) in cis, and three had conventional RHCE*cE, presumed in cis. The low population frequency of both variant alleles strongly suggest a genetic association between them. Description of in cis associations is important for the identification of antibodies to high-frequency antigens in the Rh system, and facilitates matching efforts for patients with rare or uncommon genotypes. References 1. Transfusion 50S, S110-040C 2. Transfusion 50S, S112-040C 3. Vox Sanguinis, 101 Suppl. 4D-S21-05