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Mimura T, Relationship between HLA and retinopathy in patients with type 1 diabetes
HLA-A, -B, -C, -DR, and -DQ typing of blood samples was conducted using
standard microcytotoxicity methods.
For comparisons between the two groups, we applied the chi-square test of
independence or Fisher's exact probability test. The unpaired t-test was used for
comparing mean values. The level of significance was set at p < 0.05. All analyses
were performed using the Stat View statistical software package (Abacus Concepts,
Berkeley, CA, U.S.A.).
RESULTS
The frequency of HL-DR3, -DR4, and -DR9 was significantly higher in the non-DR
group than in the control group, while the frequency of HLA-B51, -Cw3, -Cw10, -DR2,
-DR13, -DR14, and -DQ1 was higher in the control group (Tables 2 and 3). The
frequency of HLA-B62, -Cw4, and -DQ4 was significantly higher in the PDR group
than in the non-DR group (P = .0020, P = .048, and P = .0026, Tables 2 and 3).
The B62-Cw4 haplotype frequency was 6.6% in the PDR group, while that for
B62-DQ4 was 26.7% and Cw4-DQ4 was 16.7%. The DR4-DQ4 haplotype frequency
was significantly higher in the DR (-) group (32%) or in the PDR group (46.6%) than
in the control group (10%) (P = .0064 and P = .000030, Table 4). The Cw4-DR4-DQ4
