PURPOSE. Some patients with anterior uveitis (AU) ankylosing spondylitis (A
S) and are HLA-B27 class I-positive. The purpose of this study was to inves
tigate whether there are differences in HLA at the allele level among each
group of patients with AU.
METHODS. Seventy-three patients with AU were studied. They were classified
into three groups: 31 with AS-associated AU. 14 with HLA-B27-associated AU,
and 28 with idiopathic AU. Three control groups without AU were used: 138
random subjects, 33 HLA-B27-positive healthy subjects, and 19 HLA-B27-posit
ive patients with AS. DRB1 and DQB1 genotyping was performed using polymera
se chain reaction (PCR)-single-strand conformation polymorphism (PCR-SSCP)
and PCR-restriction fragment length polymorphism. HLA-B27 subtype was deter
mined by PCR-SSCP.
RESULTS. There was no difference in the frequency of any class I antigen ex
cept HLA-B27 among the patients studied. The frequencies of HLA-DR12 in AS-
associated AU and HLA-DR1 in HLA-B27-associated AU showed an increase. In H
LA-R27-associated AU, DRB1*0101 and DQB1*0501 were increased compared with
HLA-B27-positive control subjects. When HLA-B27 subtype distribution was co
mpared among the groups, the proportion of B*2704 was significantly lower i
n HLA-B27-associated AU (P = 0.037), however, such a difference was nut pre
sent in AS-associated groups.
CONCLUSIONS. These results indicated that B*2704 seemed to be less suscepti
ble to AU compared with B*2705 in Japanese subjects. The increase of HLA-DR
12 and HLA-DR1 in AU may be caused by linkage disequilibrium with B*2704 an
d B*2705, respectively.