MARCIA REGINA DEZAN
Projetos de Pesquisa
Unidades Organizacionais
LIM/31 - Laboratório de Genética e Hematologia Molecular, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
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- Variant genotypes associated with reduced expression of RhCE antigens among Brazilian blood donors(2021) DEZAN, Marcia Regina; OLIVEIRA, Valeria B.; CONRADO, Marina C. A. V.; ROCHA, Mateus Cardoso da; LUZ, Fabio; GALLUCCI, Antonio; PEREIRA, Alexandre C.; KRIEGER, Jose E.; ROCHA, Vanderson; MENDRONE-JUNIOR, Alfredo; DINARDO, Carla LuanaBackground The genetic diversity of the RHCE gene locus has been explored in diverse populations of different racial backgrounds. Data referring to the diversity of RHCE encoding weakened expression of C, c, E, and e in multiethnic populations is still incomplete. Methods Samples from Brazilian blood donors presenting reduced expression of C, c, E, or e on gel method were selected for the study. All exons and flanking introns of RHCE were genotyped though direct Sanger sequencing for the included donors. Results Sixty-six donors were included: 23 with weak C, 22 with weak c, 6 with weak E, 14 with weak e, and 1 with weak c and E. Among the samples with weak C, the following altered RH*C were encountered: RHCE*CeMA (n = 3), RHCE*Ce941C (n = 1), and RHCE*CeVA (n = 1). RHD*D-CE(4-7)-D was detected in six cases, RHCE*CE was presumably present in five cases, and seven cases were unexplained. Two altered alleles underlay the weak c phenotype: RHCE*ceJAL (n = 20) and RHCE*ce340T (n = 2), and two altered RHCE justified weak e: RHCE*ceMO (n = 6) and RHCE*ceJAL (n = 8). Three variant RHCE were associated with weak E: RHCE*cEJU (n = 4), RHCE*cE382C (n = 1), and RHCE*cEIV (n = 1). The RHCE*cE905A justified one case of weak c and E. Conclusion We describe the distribution of RHCE variants found in association with weak expression of C, c, E, and e in blood donors of multiethnic origin, which differs in comparison to that previously reported for people of African or Caucasian descent.
- Diversity of variant alleles encoding Kidd, Duffy, and Kell antigens in individuals with sickle cell disease using whole genome sequencing data from the NHLBI TOPMed Program(2021) DINARDO, Carla L.; OLIVEIRA, Theo G. M.; KELLY, Shannon; ASHLEY-KOCH, Allison; TELEN, Marilyn; SCHMIDT, Luciana C.; CASTILHO, Shirley; MELO, Karla; DEZAN, Marcia R.; WHEELER, Marsha M.; JOHNSEN, Jill M.; NICKERSON, Deborah A.; JAIN, Deepti; CUSTER, Brian; PEREIRA, Alexandre C.; SABINO, Ester C.Background Genetic variants in the SLC14A1, ACKR1, and KEL genes, which encode Kidd, Duffy, and Kell red blood cell antigens, respectively, may result in weakened expression of antigens or a null phenotype. These variants are of particular interest to individuals with sickle cell disease (SCD), who frequently undergo chronic transfusion therapy with antigen-matched units. The goal was to describe the diversity and the frequency of variants in SLC14A1, ACKR1, and KEL genes among individuals with SCD using whole genome sequencing (WGS) data. Study Design and Methods Two large SCD cohorts were studied: the Recipient Epidemiology and Donor Evaluation Study III (REDS-III) (n = 2634) and the Outcome Modifying Gene in SCD (OMG) (n = 640). Most of the studied individuals were of mixed origin. WGS was performed as part of the National Heart, Lung, and Blood Institute's Trans-Omics for Precision Medicine (TOPMed) program. Results In SLC14A1, variants included four encoding a weak Jk(a) phenotype and five null alleles (JK(null)). JKA*01N.09 was the most common JK(null). One possible JK(null) mutation was novel: c.812G>T. In ACKR1, identified variants included two that predicted Fy(x) (FY*X) and one corresponding to the c.-67T>C GATA mutation. The c.-67T>C mutation was associated with FY*A (FY*01N.01) in four participants. FY*X was identified in 49 individuals. In KEL, identified variants included three null alleles (KEL*02N.17, KEL*02N.26, and KEL*02N.04) and one allele predicting K-mod phenotype, all in heterozygosity. Conclusions We described the diversity and distribution of SLC14A1, ACKR1, and KEL variants in two large SCD cohorts, comprising mostly individuals of mixed ancestry. This information may be useful for planning the transfusion support of patients with SCD.