Association between C1q gene polymorphisms and autoimmune thyroid diseases

ABSTRACT Objective In the present study, we aimed to assess the associations of C1q gene polymorphisms with autoimmune thyroid diseases (AITD) susceptibility. Subjects and methods A set of 1,003 AITD patients (661 with Graves' disease and 342 with Hashimoto's thyroiditis) and 880 ethnically- and geographically-matched controls from Chinese Han population were included. Five common single nucleotide polymorphisms (SNPs) (rs294185, rs292001, rs682658, rs665691 and rs294179) in C1q gene locus were genotyped. Frequencies of genotypes and alleles were compared between patients and controls, and haplotype analysis was also performed. Results There was no statistically significant difference between AITD patients and controls in the frequencies of alleles of rs294185 (P = 0.41), rs292001 (P = 0.71), rs682658 (P = 0.68), rs665691 (P = 0.68) and rs294179 (P = 0.69). There was also no statistically significant difference between AITD patients and controls in the frequencies of genotypes of rs294185 (P = 0.72), rs292001 (P = 0.89), rs682658 (P = 0.83), rs665691 (P = 0.90) and rs294179 (P = 0.43). Stratified analyses showed that none of those five SNPs in C1q gene were associated with Graves' disease or Hashimoto's thyroiditis (all P values > 0.05). Haplotype analysis revealed that there were no obvious genetic associations of C1q gene polymorphisms with AITD susceptibility. Conclusions We, for the first time, identified the associations between C1q gene SNPs and AITD, and our findings suggested that five common SNPs in C1q gene were not associated with AITD susceptibility in Chinese Han population.

Association between C1q gene polymorphisms and autoimmune thyroid diseases.

OBJECTIVE: In the present study, we aimed to assess the associations of C1q gene polymorphisms with autoimmune thyroid diseases (AITD) susceptibility. SUBJECTS AND METHODS: A set of 1,003 AITD patients (661 with Graves' disease and 342 with Hashimoto's thyroiditis) and 880 ethnically- and geographically-matched controls from Chinese Han population were included. Five common single nucleotide polymorphisms (SNPs) (rs294185, rs292001, rs682658, rs665691 and rs294179) in C1q gene locus were genotyped. Frequencies of genotypes and alleles were compared between patients and controls, and haplotype analysis was also performed. RESULTS: There was no statistically significant difference between AITD patients and controls in the frequencies of alleles of rs294185 (P = 0.41), rs292001 (P = 0.71), rs682658 (P = 0.68), rs665691 (P = 0.68) and rs294179 (P = 0.69). There was also no statistically significant difference between AITD patients and controls in the frequencies of genotypes of rs294185 (P = 0.72), rs292001 (P = 0.89), rs682658 (P = 0.83), rs665691 (P = 0.90) and rs294179 (P = 0.43). Stratified analyses showed that none of those five SNPs in C1q gene were associated with Graves' disease or Hashimoto's thyroiditis (all P values > 0.05). Haplotype analysis revealed that there were no obvious genetic associations of C1q gene polymorphisms with AITD susceptibility. CONCLUSIONS: We, for the first time, identified the associations between C1q gene SNPs and AITD, and our findings suggested that five common SNPs in C1q gene were not associated with AITD susceptibility in Chinese Han population.

The increased but non-predominant expression of Th17- and Th1-specific cytokines in Hashimoto’s thyroiditis but not in Graves’ disease

Hashimoto’s thyroiditis (HT) is considered to be mediated mainly by Th1 cells, but it is not known whether Graves’ disease (GD) is associated with Th1 or Th2 predominance. Th17 cells, a novel subset of Th cells, play a crucial role in the pathogenesis of various autoimmune disorders. In the present study, the expression of IL-17A and IFN-γ was investigated in patients with HT or GD. mRNA expression of IL-17A and IFN-γ in peripheral blood mononuclear cells (PBMC) from 43 patients with autoimmune thyroid disease (AITD) and in thyroid tissues from 40 AITD patients were measured by real-time qRT-PCR. The protein expression of IL-17A and IL-23p19 was examined by immunohistochemistry in thyroid tissues from 28 AITD patients. The mRNA levels of IL-17A and IFN-γ were higher in both PBMC and thyroid tissues of HT patients than in controls (mRNA levels are reported as the cytokine/β-actin ratio: IL-17 = 13.58- and 2.88-fold change and IFN-γ = 16.54- and 2.74-fold change, respectively, P < 0.05). Also, the mRNA levels of IL-17A and IFN-γ did not differ significantly in GD patients (P > 0.05). The high protein expression of IL-17A (IOD = 15.17 ± 4.8) and IL-23p19 (IOD = 16.84 ± 7.87) in HT was confirmed by immunohistochemistry (P < 0.05). The similar high levels of IL-17A and IFN-γ suggest a mixed response of Th17 and Th1 in HT, where both cells may play important roles in the destruction procedure by cell-mediated cytotoxicity.

The increased but non-predominant expression of Th17- and Th1-specific cytokines in Hashimoto's thyroiditis but not in Graves' disease.

Hashimoto's thyroiditis (HT) is considered to be mediated mainly by Th1 cells, but it is not known whether Graves' disease (GD) is associated with Th1 or Th2 predominance. Th17 cells, a novel subset of Th cells, play a crucial role in the pathogenesis of various autoimmune disorders. In the present study, the expression of IL-17A and IFN-γ was investigated in patients with HT or GD. mRNA expression of IL-17A and IFN-γ in peripheral blood mononuclear cells (PBMC) from 43 patients with autoimmune thyroid disease (AITD) and in thyroid tissues from 40 AITD patients were measured by real-time qRT-PCR. The protein expression of IL-17A and IL-23p19 was examined by immunohistochemistry in thyroid tissues from 28 AITD patients. The mRNA levels of IL-17A and IFN-γ were higher in both PBMC and thyroid tissues of HT patients than in controls (mRNA levels are reported as the cytokine/ß-actin ratio: IL-17 = 13.58- and 2.88-fold change and IFN-γ = 16.54- and 2.74-fold change, respectively, P < 0.05). Also, the mRNA levels of IL-17A and IFN-γ did not differ significantly in GD patients (P > 0.05). The high protein expression of IL-17A (IOD = 15.17 ± 4.8) and IL-23p19 (IOD = 16.84 ± 7.87) in HT was confirmed by immunohistochemistry (P < 0.05). The similar high levels of IL-17A and IFN-γ suggest a mixed response of Th17 and Th1 in HT, where both cells may play important roles in the destruction procedure by cell-mediated cytotoxicity.