Three novel loci in the MHC may affect susceptibility to cervical cancer in situ, including the MICA-A5.1 allele that may cause impaired immune activation and increased risk of tumor development.

High loads of human papillomavirus (HPV) 16 and HPV 18/45 increase the risk of developing invasive cervical carcinoma, revealing higher risk in percentiles of highest viral loads for HPV 16 (odds ratio (OR) 58.7, 95% confidence interval (CI) 21.9 -151.4) compared to HPV 18/45 (OR 3.3, 95% CI 1.5 -7.2). Thus, HPV load is a type-dependent risk marker for invasive carcinoma.