Taking into consideration the published results on human breast cancer, reporting that the +4259T/G polymorphism (rs1036199) in the exon 3 of the TIM-3 gene is associated with an increased Ki-67 index and with metastatic disease, leading to a worse prognosis and disease progression [36], the nucleotide sequence of the exon 3 was analyzed in 19 tumor samples. This evidence concerns the gene MKI67 and breast carcinoma.