Galectin-3 is a multifunctional protein highly expressed in thyroid cancer. The galectin-3 gene (LGALS3) has several annotated candidates SNPs, however the relationship between galectin-3 SNPs and specific phenotypic variations relevant to health has not been evaluated. In this study, we investigated SNPs in the galectin-3 gene and a putative association with thyroid tumorigenesis. The presence of LGALS3 SNPs in thyroid carcinoma cell lines (NPA, TPC-1, WRO, ARO), thyroid tissues of 55 patients with multinodular goiter or papillary carcinoma diagnosis and lymphocytes of peripherical blood of 45 healthy individuals was evaluated by sequencing and SSCP. The analysis of LGALS3 coding sequence showed that the T98P site presents a great genotypic variation, since we observed both homozygous (AA or CC) and heterozygous (AC) patterns. In thyroid carcinoma cell lines, the genotype of NPA in the LGALS3 T98P site is CC, while TPC-1, WRO and ARO are AC. 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