ABSTRACT
TPO gene variations are one of the causes of thyroid autoimmune diseases. The aim of this study was to examine the association between the T1936C, T2229C and A2257C SNPs [single nucleotide polymorphisms]of the TPO gene and Anti-TPO level. In this case-control study, 188 individuals [86 males and 102 females], aged 20-80 years, were randomly selected from the Tehran Lipid and Glucose Study population [TLGS]. A2257C and T2229C SNPs were detected with RFLP by use of BsrI and Eco57I as restrictive enzymes respectively, while the T1936C SNP was determined with ARMS-PCR. In the presence of the C allele of T1936C, Anti-TPO level was significantly increased [CC: 238 +/- 43.3, CT: 47.7 +/- 15.9, TT: 74.1 +/- 11.3 IU/L; p 0.002]; however, it disappeared after adjustment for sex and age [p 0.059]. No significant difference, before and after adjustment, was found in Anti-TPO level in the presence of T2229C SNP [CC: 129.1 +/- 24.5, CT: 43.5 +/- 12.6, TT: 126.5 +/- 13.8 IU/L; p 0.196]. The association of A2257C with Anti-TPO level was only significant after adjustment for sex and age [p 0.007],and between the ATC ,CTT haplotypes and Anti-TPO level ,the association was significant [p 0.023, 0.021]; however, the association it was dominant between CTT and anti-TPO concentration was significant only after adjustment for sex [p 0.014]. The result of this study, showed age and sex as potential confounders which could modify the association between TPO polymorphisms and Anti-TPO level in a Tehranian population