5' regulatory nucleotide sequence of an HLA-A*0101null allele.
We have previously demonstrated an HLA-A*0101null allele segregating in a family with the HLA-B8, -Cw7, -DR3, -DR52, -DQ2 haplotype. In the present study the regulatory elements with known transcription enhancement activity of the silenced HLA-A*0101 allele were analyzed. In the enhancer B element, a T was substituted for a C at position - 106, whereas no other alterations were found in the adjacent 5' section of the HLA-A*0101null allele. This substitution was not seen in the enhancer B elements of the corresponding genes involved in normal HLA-A*0101 membrane expression. Comparison of enhancer B element sequences of classical functional major histocompatibility complex (MHC) class I alleles demonstrated a high degree of conservation. In contrast, many MHC class I pseudogenes showed mutation in their enhancer B boxes. These results may indicate that the single mutation detected in the enhancer B element plays a pivotal role in the abolishment of membrane expression of the HLA-A*0101null allele.
Lardy
N M
NM
Department of HLA Diagnostics, Central Laboratory of the Netherlands Red Cross Blood Transfusion Service and Laboratory for Experimental and Clinical Immunology of the University of Amsterdam, Plesmanlaan 125, 1066 CX, The Netherlands.
Otting
N
N
van der Horst
A R
AR
Bontrop
R E
RE
de Waal
L P
LP
D000483:Alleles; D001483:Base Sequence; D015234:HLA-A Antigens / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA
D015234:HLA-A Antigens