In another study, serum selenium levels were determined in 95 patients with lung cancer and the genotypes of four selenoprotein genes (GPX1, GPX4, TXNRD2, and SEP15) were determined, demonstrating that a selenium level less than 60 μg·L−1 is associated with a higher risk of lung cancer [106]. The gene discussed is TXNRD2; the disease is lung carcinoma.