The role of TYMS 28-bp tandem repeat polymorphisms was not associated with acute lymphoblastic leukemia and lung cancer risk development (Oosterom et al., 2018; Stanisławska-Sachadyn et al. 2019); however, a study in the Brazilian population revealed increased risk association between the 2R/2R and 2R/3R variants in sporadic and hereditary breast cancer development, which was not in accordance with the results of our study (da Silva Nogueira et al., 2012). This evidence concerns the gene TYMS and breast cancer.