A novel ABO allele with a 21-bp duplication identified in two unrelated European individuals with weak A expression.
Transfus Med
; 30(6): 508-512, 2020 Dec.
Article
en En
| MEDLINE
| ID: mdl-33103288
OBJECTIVES: To carry out genetic and serological analyses of a Swiss blood donor and a Danish patient carrying an aberrant ABO phenotype with weak A expression. BACKGROUND: ABO is the most clinically important blood group system but also one of the most complex. The system antigens are determined by carbohydrate structures generated by A and B glycosyltransferases encoded by the ABO gene. Genetic variants of ABO may encode a glycosyltransferase with reduced activity, leading to weak expression of A antigen. METHODS: Samples from two individuals were examined using genetic testing and extended immunohaematological evaluation, including standard serological methods, flow cytometry and analysis of plasma glycosyltransferase activity. RESULTS: Both individuals were serologically determined to be Aweak B. Genetic testing revealed that both were heterozygous for a novel ABO*A1.01-like allele with an in-frame duplication of 21 nucleotides in exon 7 (c.543_563dup), leading to the insertion of seven amino acids (QDVSMRR). Flow cytometric testing of native red blood cells (RBCs) showed very weak A antigen expression. This was in accordance with the enzyme activity test. CONCLUSION: In summary, we describe a novel A allele with a duplication of 21 nucleotides in exon 7 that significantly decreases the enzyme activity and leads to very weak expression of A antigen. (200 words).
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sistema del Grupo Sanguíneo ABO
/
Exones
/
Alelos
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Eritrocitos
/
Heterocigoto
Tipo de estudio:
Prognostic_studies
Límite:
Aged
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Humans
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Male
País/Región como asunto:
Europa
Idioma:
En
Revista:
Transfus Med
Asunto de la revista:
HEMATOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Dinamarca
Pais de publicación:
Reino Unido