RT Journal Article
SR Electronic
T1 Structural analysis of an HLA-B27 functional variant, B27d, detected in American blacks.
JF The Journal of Immunology
JO J. Immunol.
FD American Association of Immunologists
SP 3396
OP 3401
VO 139
IS 10
A1 Rojo, S
A1 Aparicio, P
A1 Hansen, J A
A1 Choo, S Y
A1 López de Castro, J A
YR 1987
UL http://www.jimmunol.org/content/139/10/3396.abstract
AB The structure of a new functional variant B27d has been established by comparative peptide mapping and radiochemical sequencing. This analysis completes the structural characterization of the six known histocompatibility leukocyte antigen (HLA)-B27 subtypes. The only detected amino acid change between the main HLA-B27.1 subtype and B27d is that of Tyr59 to His59. Position 59 has not been previously found to vary among class I HLA or H-2 antigens. Such substitution accounts for the reported isoelectric focusing pattern of this variant. HLA-B27d is the only B27 variant found to differ from other subtypes by a single amino acid replacement. The nature of the change is compatible with its origin by a point mutation from HLA-B27.1. Because B27d was found only in American blacks and in no other ethnic groups, it is suggested that this variant originated as a result of a mutation of the B27.1 gene that occurred within the black population.