RESUMO
The novel HLA-B*53:39 allele differs from HLA-B*53:01 by a single nucleotide substitution at codon 45 (ACG>AAG).
Assuntos
Genes MHC Classe I , Antígenos HLA-B/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Códon/genética , Feminino , Sangue Fetal , Guadalupe , Humanos , Recém-Nascido , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Gravidez , Alinhamento de Sequência , Homologia de SequênciaRESUMO
We report the identification of a new HLA-A null allele, HLA-A*0115N. This null allele has been identified within the A*01 group by a combination of serological and molecular typing [Polymerase chain reaction (PCR) sequence-specific primers, PCR sequence-specific oligoprobes and sequence-based typing (SBT)] in a potential intrafamilial bone marrow donor from Martinique (French West Indies). To characterize this A*01 null allele, we performed DNA typing by PCR-SBT on genomic DNA from the beginning of exon 2 (position 84) through the end of the exon 4 (position 895) and revealed a nucleotide deletion at the end of the exon 3. This sole difference between the new allele and the HLA-A*0101 generates a premature stop codon (TGA) in the beginning of exon 4. This deletion most likely explains the lack of cell surface expression of the encoded protein despite the presence of A*01 allele. The absence of correct expression of the antigen on the cell surface was confirmed by one-dimensional isoelectric focusing (1D-IEF). To date, this is the fourth null allele described within the A*01 group.