title: HLA-B*27 subtypes in Northern and Northeastern Thais, Karens, and Bamars determined by a high-resolution PCR-SSP technique.
abstract: Human leukocyte antigens (HLA), class I, are a group of antigens expressed on most nucleated cell surfaces. They transport endogenous peptides to the cell surface for recognition by T-cell receptors. Their functions are involved in immune responses. Many diseases are associated with HLA alleles, especially HLA-B*27 that is strongly associated with ankylosing spondylitis (AS). HLA-B*27 consists of 42 subtypes. Different subtypes of HLA-B*27 were reported in different ethnic groups of AS patients. In this study, a high-resolution polymerase chain reaction-sequence-specific primer technique has been developed to define all the HLA-B*27 subtypes with a total of 29 primer mixtures. Two of the primer mixes were used to detect the HLA-B*27-specific group, and 27 primer mixes were used to identify 42 subtypes (B*2701-B*2721 and B*2723-B*2743). The HLA-B*27-group-specific primers have been tested in unrelated healthy subjects; 846 Northeastern Thais (NET), 334 Northern Thais (NT), 264 Karens, and 310 Bamars. Sixty-three NET (phenotype frequency, PF = 7.4%), 24 NT (PF = 7.1%), 5 Karens (PF = 1.8%), and 12 Bamars (PF = 3.9%) were positive for HLA-B*27. Only B*2704 was found in Karens, whereas B*2704, B*2705/37/39, B*2706, and B*2707 were found in NET and NT. In Bamars, B*2704, B*2705/37/39, B*2706, and B*2725 were found. The distribution of HLA-B*27 subtypes was compared with other studies in Asian and Caucasian populations. Significant differences of the distribution of HLA-B*27 subtypes were found in most of the populations. This study established a simple technology for HLA-B*27 subtyping and provided basic information for anthropology and further studies in disease associations.
authors.affiliation: Biomedical Science Program, Faculty of Graduate School, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: M
authors.initials: M
authors.lastname: Duangchanchot
authors.forename: C
authors.initials: C
authors.lastname: Puapairoj
authors.forename: A
authors.initials: A
authors.lastname: Romphruk
authors.forename: C
authors.initials: C
authors.lastname: Kongmaroeng
authors.forename: C
authors.initials: C
authors.lastname: Leelayuwat
authors.forename: A V
authors.initials: AV
authors.lastname: Romphruk
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics*; D004194:Disease / Q000235:genetics*; D005091:Exons; D005787:Gene Frequency; D005838:Genotype; D015796:HLA-B27 Antigen / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*
chemical_list: D015796:HLA-B27 Antigen