Brendle et al. investigated whether SNPs in CIN-related genes affect BC risk and clinical outcomes in a Swedish cohort of BC cases and found that for the SNP rs1862392 in the PTTG1 gene, carriers of the TA genotype were more likely to have tumors with regional lymph node metastasis compared to carriers of the wild-type genotype 89. This evidence concerns the gene PTTG1 and cervical squamous intraepithelial neoplasia.