Analysis of HLA-B27, investigating of the susceptibility of AS and AAU

强直性脊柱炎(AS)与人类白细胞抗原B27的相关性在许多国家都有报道，但在日本非常罕见，因为与高加索人相比，日本人中人类白细胞抗原B27的频率也很低。我们调查了46例日本AS患者和59例AAU患者；24例AS和AAU患者，共计81例，其中44例携带有HLA-B27。采用聚合酶链式反应-单链构象多态性方法对B27DNA进行亚型分析，并用全自动测序仪对其氨基酸序列进行验证。用聚合酶链式反应-单链构象多态和限制性片段长度多态性方法进行第二类DNA分型。我们估计了人类白细胞抗原B27各亚型与II类等位基因(DR、DQ基因座)之间的连锁不平衡。我们发现了两种亚型：B^&lt；**&gt；2704和B^&lt；**&gt；2705。前者34例(77.3%)，后者10例(22.7%)。在AS患者、AAU患者和B27阳性对照中，未发现两种亚型之间的差异。然后将AS患者分为AAU组和非AAU组，两组B27亚型频率基本相同，但HLADR8频率差异有统计学意义，AAU患者HLADR8频率升高(p&lt；0.0005)。这一结果可能提示AS患者AAU的易感性受人类白细胞抗原DR8的影响。含有人类白细胞抗原A、B、DR单倍型的HLA-B27的单倍型频率正在调查中。

The strong association between Ankylosing Spondylitis (AS) and HLA-B27 has been reported from many countries, but, very rare from Japan, because AS as well as the frequency of HLA-B27 is rare in Japan as compared with Caucasians. HLA-B27 is also known to be associated with acute anterior uveitis (AAU) which is often complicated with AS.We investigated 46 Japanese patients with AS and 59 with AAU ; 24 patients with AS and AAU,a total number of 81 patients, of which 44 patients carried HLA-B27. PCR-SSCP was employed for B27 DNA subtyping, and the amino acid sequence was confirmed by automated sequencer. We also performed class II DNA typing using PCR-SSCP and-RFLP method. We estimated the linkage disequilibrium between each subtype of HLA-B27 and class II alleles (DR,DQ locus). We found two subtypes of HLA-B27, B^<**>2704 and B^<**>2705. The former was found in 34 (77.3%) patients and the latter in 10 (22.7%). We could not find any differences in the frequencies of 2 HLA-B27 subtypes among AS patients, AAU patients and B27 positive controls. Then AS patients were divided into two groups ; with AAU and without AAU.The frequencies of B27 subtypes were almost equal between the two groups, however, we found a significant difference in the frequency of HLA-DR8, which was increased in the patients with AAU (p<0.0005). This result may suggest that the susceptibility of AAU in the AS patients is influenced by HLA-DR8. HLA-B27 containing HLA-A,B,DR haplotypes frequencies are now being investigated.