It could be carried out in several ways: (1) through the analysis of ST6GAL1 and Tg co-expression in various types of thyroid cancers and other thyroid pathologies, (2) with the measurement of ST6GAL1 plasma levels in patients with thyroid cancers and other thyroid pathologies and correlation with plasma Tg levels, and (3) with the analysis of the distribution of different ST6GAL1 genotypes associated with plasma Tg levels between patients with different thyroid pathologies and healthy controls. The gene discussed is ST6GAL1; the disease is thyroid cancer.