C Prisco Arnoni1, J Guilhem Muniz2, T A de Paula Vendrame2, R de Medeiros Person2, F Roche Moreira Latini2, L Castilho3. 1. Technical scientific department Colsan - Associação Beneficente de Coleta de Sangue, São Paulo, SP, Brazil. carine.arnoni@colsan.org.br. 2. Technical scientific department Colsan - Associação Beneficente de Coleta de Sangue, São Paulo, SP, Brazil. 3. Molecular Immunohematology Laboratory Hemocentro - Unicamp, Campinas, SP, Brazil.
Abstract
BACKGROUND: The high homology and opposite orientation of RH genes promote rearrangements between them and generate a large number of RHD and RHCE variants which can be inherited together. Searching of RHD-CE genotypes predicting partial antigens in donors is of interest in order to find more closely matched donors for African descent patients. This study aimed to evaluate a molecular approach to search for RhCE variants in a cohort of individuals with altered expression of D antigen and determine the association of RH variant alleles in Brazilian blood donors. METHODS: From 80,961 blood samples tested, 421 with atypical D typing results were studied. The samples were phenotyped for C, c, E, e antigens. Rh variants were identified using molecular techniques. RESULTS: All 421 samples had altered RHD alleles, being 56·3% of them partial D. Among them, 94·9% presented variant RHCE*ce and the most common associations were: RHD*weak D type 4.2.2 with RHCE*ceAR; RHD*DAR linked to RHCE*ceVS.02; RHD*weak D type 4.0 linked to RHCE*ceVS.02 and RHCE*ce (c.48C, c.105T, c.733G, c.744C, c.1025T). Among the samples with RhCE variants, 10·6% predict partial c, partial e, hr(B) - and/or hr(S) - and 100% express low prevalence antigens. CONCLUSION: Targeting individuals with altered expression of D antigen can be a good strategy for finding donors with RhCE variants. In our study 94·9% of the partial D samples revealed altered RHCE variant alleles and 5·7% of the samples with altered RHD allele predicted partial c, partial e and the lack of the high prevalence hr(B) and hr(S) antigens.
BACKGROUND: The high homology and opposite orientation of RH genes promote rearrangements between them and generate a large number of RHD and RHCE variants which can be inherited together. Searching of RHD-CE genotypes predicting partial antigens in donors is of interest in order to find more closely matched donors for African descent patients. This study aimed to evaluate a molecular approach to search for RhCE variants in a cohort of individuals with altered expression of D antigen and determine the association of RH variant alleles in Brazilian blood donors. METHODS: From 80,961 blood samples tested, 421 with atypical D typing results were studied. The samples were phenotyped for C, c, E, e antigens. Rh variants were identified using molecular techniques. RESULTS: All 421 samples had altered RHD alleles, being 56·3% of them partial D. Among them, 94·9% presented variant RHCE*ce and the most common associations were: RHD*weak D type 4.2.2 with RHCE*ceAR; RHD*DAR linked to RHCE*ceVS.02; RHD*weak D type 4.0 linked to RHCE*ceVS.02 and RHCE*ce (c.48C, c.105T, c.733G, c.744C, c.1025T). Among the samples with RhCE variants, 10·6% predict partial c, partial e, hr(B) - and/or hr(S) - and 100% express low prevalence antigens. CONCLUSION: Targeting individuals with altered expression of D antigen can be a good strategy for finding donors with RhCE variants. In our study 94·9% of the partial D samples revealed altered RHCE variant alleles and 5·7% of the samples with altered RHD allele predicted partial c, partial e and the lack of the high prevalence hr(B) and hr(S) antigens.
Authors: Thamy C Souza Silva; Bruno R Cruz; Sidneia S Costa; Akemi K Chiba; Melca M O Barros; Dante M Langhi; José O Bordin Journal: Blood Transfus Date: 2020-07 Impact factor: 3.443
Authors: Carla L Dinardo; Shannon Kelly; Marcia R Dezan; Ingrid H Ribeiro; Shirley L Castilho; Luciana C Schimidt; Maria do C Valgueiro; Liliana R Preiss; Brian Custer; Ester C Sabino; Connie M Westhoff Journal: Transfusion Date: 2019-08-13 Impact factor: 3.157