A new silent mutation at codon 35 in exon 2 yielding DRB1*04012 allele

Abstract

Currently at least 23 different HLA-DRB 1*04 alleles have been defined by the WHO HLA Nomenclature Committee for HLA Factors (1,2). Here, we report the detection of a new DR4 allele (Accession No X9685 1) officially named DRB 1 *04012. Surprisingly, this new allele was discovered independently, and nearly simultaneously, in two unrelated Caucasian individuals of Belgian origin. The first one (UCL-MS) was a leukemic patient awaiting bone marrow transplantation. He was HLA typed at the Immunohematology Laboratory of the UCL. The second individual (VUB-BP) was HLA typed by the HLA Laboratory of the AZ-VUB after presenting with fertility problems.In the two cases, this new allele was detected because both samples yielded an unusual hybridization pattern in the INNO LiPA DRB typing kit (Innogenetics N.V., Zwijndrecht, BeIgium). For the UCL-MS sample, the positive probes were 4-15-1 8-19-25-27-28, suggesting the presence of the al-The name DRBl"04012 has been officially assigned by the WHO Nomenclature Committee in June 1996. This follows the agreed policy that, subject to the conditions stated in the most recent Nomenclature Report ( l ) , names will be assigned to new sequences as they are identified. A list of such new names will be published in the following report,