Similarly, there were 80 AA genotypes, 27 AC genotypes and 3 CC genotypes in normal group, 52 AA, 39 AC and 25 CC in CIN group, and 26 AA, 64 AC and 56 TT in cancer group for MTHFR A1298C genotypes, respectively (Fig. 2c). The gene discussed is MTHFR; the disease is cervical squamous intraepithelial neoplasia.