Polygenic risk scores and breast cancer risk prediction
by Eleanor Roberts,
Sacha Howell, Gareth Evans
The Breast: VOLUME 67, P71-77, FEBRUARY
2023
Abstract
Polygenic Risk Scores (PRS) are a major component of
accurate breast cancer risk prediction and have the potential to improve
screening and prevention strategies. PRS combine the risk from Single
nucleotide polymorphisms (SNPs) associated with breast cancer in Genome Wide
Association Studies (GWAS) and explain over 30% of breast cancer heritability.
When incorporated into risk models, the more personalised risk assessment
derived from PRS, help identify women at higher risk of breast cancer
development and enables the implementation of stratified screening and
prevention approaches. This review describes the role of PRS in breast cancer
risk prediction including the development of PRS and their clinical
application. We have also examined the role of PRS within more well-established
risk prediction models which incorporate known classic risk factors and discuss
the interaction of PRS with these factors and their capacity to predict breast
cancer subtypes. Before PRS can be implemented on a population-wide scale,
there are several challenges that must be addressed. Perhaps the most pressing
of these is the use of PRS in women of non-White European origin, where PRS
have been shown to have attenuated risk prediction both in discrimination and
calibration. We discuss progress in developing and applying PRS in non-white
European populations. PRS represent a significant advance in breast cancer risk
prediction and their further development will undoubtedly enhance
personalisation.