A new HLA-B*27 allele (B*2719) identified in a Lebanese patient affected with ankylosing spondylitis

Eighteen different HLA-B*27 alleles (B*2701-B2718) have so far been recogni zed by the WHO Nomenclature Committee for Factors of the BLA System. Freque ncy and disease association of these alleles with spondyloarthropathies dif fer among ethnic groups. We describe here a novel HLA-B*27 subtype identifi ed in a Lebanese patient suffering from ankylosing spondylitis (AS). This n ew variant differs from the common HLA-B*2705 DNA sequence at five differen t nucleotide positions. These nucleotide changes lead to three amino acid d ifferences in the alpha2 domain; Thr to Ile at position 94, Leu to Ile at p osition 95 and Asn to Arg at position 97. Since this novel allele is encoun tered in an AS patient, the associated sequence changes are not expected to affect significantly neither the presentation of a putative arthritogenic peptide nor the conformation-dependent recognition by effector cells.