HLA-A*02010102L: a laborious assignment.

Laboratoire d'histocompatibilité, Vandoeuvre-les-Nancy, France.
Tissue Antigens (Impact Factor: 2.93). 12/2006; 68(5):442-5. DOI: 10.1111/j.1399-0039.2006.00682.x
Source: PubMed

ABSTRACT In the present report we describe the laborious identification of the A*02010102L allele found in three healthy individuals of a French family who have shown a reduced A2 antigen expression using serological tests since the 1980s. PCR-SSP typing showed a classical A*0201 allele. Sequencing of exons 2, 3 and 4 confirmed this assignment. Sequencing of the whole gene (promoter, introns and exons 1-8) revealed one single point mutation (T to C) at position -101 in the enhancer B element region compared to the A*02010101 allele. This single mutation appears to be related to the reduced expression of the A2 antigen. This allele segregates with the haplotype Cw*12, B44, DR7, DQ2, which is different to the one described earlier.

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