Objective: The aim of this study was to evaluate whether B7 molecules (CD80 and
CD86) could be used as genetic markers for the development of Graves’
ophthalmopathy (GO).
Design: Cross-sectional study.
Participants: 471 patients with Graves’ disease (GD) (200 patients with GO and 271
patients without GO) in a Chinese population in Taiwan.
Method: GO was identified by an endocrinologist with substantial experience in
thyroid diseases. Blood samples were taken for DNA extraction from GD subjects.
The gene polymorphism of CD80 and CD86 was genotype by polymerase chain
reaction in each patient.
Main outcome measurement: Genotypes of CD80 and CD86 polymorphism.
Results: We found that the frequency of C allele at position rs_9831894 of the CD86
gene is statistically different in patients with GD (with and without GO; chi square
test: p = 0.0017). In addition, the multifactor dimensionality reduction method was
used to identify the best gene-gene interaction to predict the risk of GO. We identified
an interaction between CD80_rs9289131 and CD86_rs9872483 (sign test, p = 0.0010).
Moreover, the GA haplotype was shown to have a protective effect in the
development of ophthalmopathy among patients with GD (odds ratio = 0.63; 95%
Confidence Interval: 0.44, 0.90). Moreover, among patients with 58 GO, the patients
carrying the GA haplotype had a lower level of free thyroxine T4 than those not
carrying the GA haplotype (p = 0.0001).
Conclusions: These results suggest that the polymorphisms of the CD86 gene may be
used as genetic markers for making the diagnosis and prognosis of GO. GO could be a
disease with complex genetic factors, resulting from the existing gene-gene
interaction found in the present study.
