title: Identification of two novel alleles HLA-B*3569 and -B*4450 and confirmation of HLA-A*2631 in the Brazilian population.
abstract: Two novel alleles, human leukocyte antigen (HLA)-B*3569, -B*4450 and a confirmatory sequence of HLA-A*2631 were identified during a routine typing for the Brazilian Bone Marrow Donor Registry. Sequence analysis of coding exons 2 and 3 revealed a single nucleotide substitution in HLA-B*3569 and two single nucleotide substitutions in HLA-B*4450, compared with closely related alleles. At the protein level, these substitutions result in a change of a single amino acid residue in each of HLA-B*3569 and -B*4450 at positions 74 (Arg > Pro) and 80 (Thr > Ile), respectively. These variations are located in the highly polymorphic region at the end of the alpha(1) domain of the HLA molecule. It appears that HLA-B*3569 arose from the analogous HLA-B*3510 through a point mutation. However, HLA-B*4450 may have arisen from HLA-B*440301 and -B*4425 by gene conversion.
authors.affiliation: Northern Ireland Histocompatibility and Immunogenetics Laboratory, Belfast City Hospital, Belfast, UK. hesham.abdeen@bll.n-i.nhs.uk
authors.forename: H
authors.initials: H
authors.lastname: Abdeen
authors.forename: C
authors.initials: C
authors.lastname: McErlean
authors.forename: M E
authors.initials: ME
authors.lastname: Moraes
authors.forename: M
authors.initials: M
authors.lastname: Romero
authors.forename: S B
authors.initials: SB
authors.lastname: Marques
authors.forename: A C
authors.initials: AC
authors.lastname: Goncales
authors.forename: E G
authors.initials: EG
authors.lastname: Guariento
authors.forename: D
authors.initials: D
authors.lastname: Middleton
mesh_terms: D019943:Amino Acid Substitution; D001938:Brazil; D005260:Female; D015234:HLA-A Antigens / Q000235:genetics*; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D008297:Male; D017354:Point Mutation
chemical_list: D015234:HLA-A Antigens; D015235:HLA-B Antigens