doi: 10.1111/j.1744-313X.2006.00629.x © 2006 The Authors Journal compilation © 2006 Blackwell Publishing Ltd, International Journal of Immunogenetics 33, 371– 373 371 Blackwell Publishing Ltd A novel HLA-B*2730 allele found in a Slovene patient affected with IgA nephropathy B. Vidan-Jeras,* S. Kunilo,* I. Fae,† A. Kandus‡ & G. F. Fischer† Summary A novel allele HLA-B*2730 and the haplotype HLA- A*03-B*2730-Cw*02-DRB1*16-DRB5 have been found in a Slovene patient and his mother. The exon 2 sequence is identical to that of HLA-B*2702, and the exon 3 sequence is identical to that of HLA-B*2719. A possible mechanism for the generation of B*2730 is a gene con- version event. We describe a novel human leucocyte antigen (HLA) allele officially named HLA-B*2730 (Marsh et al., 2005). It was discovered in a 30-year-old man of Slovene origin being on chronic haemodialysis treatment since August 2004. The novel allele and its corresponding haplotype were also determined in the patient’s mother. The patient developed end-stage renal disease as the consequence of IgA nephropathy (IgAN), one of the most common glomerulopathies in Caucasians (Nair & Walker, 2006). Patients with IgAN are usually included in the waiting lists of organ exchange organizations (Doxiadis et al., 2001). To put the patient on the kidney waiting list, HLA class I typing was performed by a standard complement- dependent microcytotoxicity assay (CDC) using commer- cial trays (Lymphotype HLA-ABC 144/2, Biotest, Dreieich, Germany), followed by polymerase chain reaction (PCR)- based amplification with sequence-specific primers (SSP) for HLA-DRB loci (Olerup SSP HLA-DRB low resolution, Genovision, Vienna, Austria). The patient appeared homo- zygous for all tested loci; the phenotype was A3; B27; Cw2; DRB1*16; DRB5. In order to rule out specificities that could have been missed, the first typings were backed up with additional PCR-SSP tests using the HLA-A, B, DR low-resolution kit (Olerup SSP HLA-A-B-DR-Combi Tray, Genovision, Vienna, Austria). While HLA-A and DR typings were confirmed, HLA-B27 could not be undoubtedly identified. Moreover, HLA-B27 high-resolution typing with SSP (Olerup SSP HLA-B27, Genovision, Vienna, Aus- tria) resulted in a reaction pattern that was not compatible with any of the then known alleles, although many of the primer pairs detected subgroups of B*27 alleles. Concerted sequencing-based typings (SBT) of the HLA- B locus were performed in two laboratories following two different protocols, respectively. In both cases, both exon 2 and exon 3 were sequenced in two directions. The locus- specific HLA-B Sequencing-Based-Typing Kit (Alle- leSEQR HLA-B, Abbott, Chicago, IL) and correspond- ing software (assign-sbt, Conexio Genomics, Applecross, WA, Australia) were used in the first labora- tory. The second laboratory applied cycle sequencing of PCR products according to the protocol of Cereb & Yang (1997), where exons 2 and 3 are amplified using primers situated in introns 1 and 3 and detect a dimorphic sequence motif. The sequencing primers are also situated in the introns. Assignment of alleles was performed using self-developed software comparing the sequence with IMGT/HLA sequence database (Robinson et al., 2003). When compared to the HLA-B*2702 sequence, HLA-B*2730 has five nucleotide substitutions leading to three amino acid exchanges. The nucleotide substitutions are all located in the exon 3 at positions 283 (Χ→Τ), 285 (C→A), 292 (A→G), 293 (T→G) and 299 (T→C). Con- sequently, all three amino acid exchanges are located in the α 2 domain at positions 94 (Thr→Ile), 95 (Leu→Ile) and 97 (Asn→Arg). The mother of the patient was typed in the same manner as the patient. While the patient appeared homozygous, the mother’s phenotype was HLA-A*01, 03; B*08, 2730; Cw*02, 07; DRB1*15, 16; DRB5. In her case, heterozygos- ity for HLA-B alleles allowed separation before sequencing. The two HLA-B alleles were separated with the primer pairs B-TA/3BIn3–37 (GGC GGG GGC GCA GGA CCT GA/ AGG CCA TCC CCG SCG ACC TAT) that amplified the B*08 and B-CG/3BIn3–37 (CGG GGG CGC AGG ACC CGG/AGG CCA TCC CCG SCG ACC TAT). The HLA type of the mother confirmed that the novel allele is part of the haplotype HLA-A*03-B*2730-Cw*02-DRB1*16-DRB5 The nucleotide sequence data on B*2730 reported in this article have been submitted to the EMBL nucleotide sequence database and were assigned the accession number AJ969956. The name B*2730 was officially assigned by the WHO Nomenclature Committee in June 2005. This follows the agreed policy that, subject to the conditions stated in the Nomenclature Report (Marsh et al., 2002), names will be assigned to the new sequences, as they are identified. Lists of such new names will be published in the following WHO Nomenclature Reports. * Tissue Typing Centre, Blood Transfusion Centre of Slovenia, Ljubljana. Slovenia, † Blood Group Serology, Medical University, Vienna, Austria, ‡ Department of Nephrology, University Clinical Centre, Ljubljana, Slovenia Received 22 May 2006; revised 05 July 2006; accepted 14 August 2006 Correspondence: Blanka Vidan-Jeras, Blood Transfusion Center of Slovenia, Slajmerjeva 6, 1000 Ljubljana, Slovenia, Tel: 386 15438 224, Fax: 386 14327 018, E-mail: blanka.vidan-jeras@ztm.si