Association of CD40 and thyroglobulin genes with later-onset Graves' disease in Taiwanese patients

Objective: Graves' disease (GD) is known to be associated with thyroglobulin (TG) and CD40 genes. Therefore, we decided to investigate the relationship of age at onset of GD with CD40 and TG gene susceptibilities in a Taiwanese population. Design and method: We analyzed the association of TG and CD40 polymorphisms with age at onset of GD in Taiwanese patients. We stratified patients into those with early onset (< 40 years; 30.3 ± 4.8 years; n = 13 5) and later onset (≥ 40 years; 52.3 ± 6.3 years; n = 80) and compared the results with those of 141 normal controls. Results: We found a significant statistical difference in the T/T genotype frequency of E33 single nucleotide polymorphism (SNP) and G/G genotype frequency of E12 SNP when compared with the control group (P < 0.001). In addition, the frequencies of the T allele and TT genotype of the CD40 SNP were found to be significantly increased in GD patients who developed GD aged over 40 years than those below 40 years (allele: X² = 5.299, P= 0.021, OR = 1.59 7; genotype: X² = 6.168, P = 0.046). By contrast, the frequencies of genotypes in the TG gene E10, E12, and E33 SNPs were not found to be significantly different in GD patients who developed GD when aged over 40 years when compared with those aged below 40 years. Conclusions: These data suggest that the T/T genotype and T allele in the CD40 gene are more likely to be associated with late-onset GD in Taiwanese patients.