A study by Zhu Li et al. investigated (SNP) polymorphisms for the genes XPG, CYP1A1, OGG1, ERCC5, ERCC1, MMP2 and MMP9 in a group of 200 patients with larynx cancer associated with heavy smoking in Shanghai (China), finding an association between SNP of genes CYP1A1 and MMP9 and larynx cancer. The gene discussed is ERCC1; the disease is laryngeal neoplasm.