Human leukocyte antigens in undifferentiated spondyloarthritis.
OBJECTIVE
Undifferentiated spondyloarthritis (USpA) is a major member of the spondyloarthritis family. Ankylosing spondylitis (AS), the prototype of the family, is a largely genetic disease, with human leukocyte antigens (HLA)-B27 being the essential gene. Other genes in the HLA region have also been implicated. The purpose of this study was to identify the alleles of the HLA-A, -B, -C, -DR, and -DQ, which are present at higher frequencies in USpA patients compared with an ethnically matched control population.


METHODS
Sixty-three Taiwanese patients with USpA were compared with 75 matched healthy controls. HLA typing was performed by polymerase chain reaction-sequence specific oligo-nucleotide genotyping.


RESULTS
The frequencies of HLA-B27, -B60, -C3, and -DR12 were strikingly higher in USpA patients compared with healthy subjects, with odds ratios of 75.4, 14.0, 9.6, and 7.0, respectively. When USpA patients with axial involvement were compared with those with peripheral arthritis, the following were more marginally frequent in those with axial involvement: HLA-B27 and -DR12 (odds ratios, 4.0 and 4.0, respectively). There was no association of HLA typing with other variables, including enthesitis, uveitis, erythrocyte sedimentation rate, and serum C-reactive protein. Interestingly, in 12 HLA-B27-negative USpA patients, HLA-B60, -C3, and -DR12 were more frequent compared with controls (odds ratios, 35, 16.2, and 8.1, respectively).


CONCLUSIONS
Similar to AS, USpA is also linked to HLA-B27. A linkage to other HLA alleles observed here, even in our HLA-B27-negative USpA patients, strongly suggests that USpA in general is a genetic disease.
Liao
Hsien-Tzung
HT
Taipei Medical University--Municipal Wan Fang Hospital, Taipei, Taiwan.
Lin
Kuan-Chia
KC
Chen
Chun-Hsiung
CH
Liang
Toong-Hua
TH
Lin
Ming-Wei
MW
Tsai
Chang-Youh
CY
Tak Yan Yu
David
D
Chou
Chung-Tei
CT
D000293:Adolescent; D000328:Adult; D005260:Female; D008040:Genetic Linkage; D006680:HLA Antigens / Q000235:genetics*; D015235:HLA-B Antigens / Q000235:genetics; D015796:HLA-B27 Antigen / Q000235:genetics; D015236:HLA-C Antigens / Q000235:genetics; D006684:HLA-DR Antigens / Q000235:genetics; D059810:HLA-DR Serological Subtypes; D006801:Humans; D008297:Male; D010865:Pilot Projects; D012189:Retrospective Studies; D025241:Spondylarthritis / Q000235:genetics* / Q000276:immunology
D006680:HLA Antigens; D015235:HLA-B Antigens; D015796:HLA-B27 Antigen; C081918:HLA-B60 antigen; D015236:HLA-C Antigens; D006684:HLA-DR Antigens; D059810:HLA-DR Serological Subtypes; C082411:HLA-DR12 antigen