SNPs in genes such as ABCB1, UGT1A1, ERCC1, TP53, MDM2, BDNF, APEX1, NUDT15, and MBL2 were associated with a higher CIN risk, whereas SNPs in genes such as CACNB4, STAM2, ABCB1, PCDH15, ALOX5AP, BCL9, and CDH7 have been associated with a higher CIA risk. Here, BDNF is linked to cervical squamous intraepithelial neoplasia.