The fact of being able to estimate the likelihood of an individual being predisposed to develop a disease constitutes an amazing opportunity to improve the clinical management of diseases affecting the general population.

In the current situation, this management is based entirely on clinical criteria, e.g. age, sex and origins, together with the parameters connected with lifestyle, such as physical activity, dietary habits and alcohol consumption, but also objective measurements of blood pressure, body mass index and substance levels in the blood (biomarkers).

Genome-wide association studies (GWAS) considering the whole genome, have overturned these habits by demonstrating that common diseases have a clearly-determined hereditary basis which, moreover, may be calculated with the aid of the polygenic risk score (PRS).

In practice, clinical factors and PRS are considered in conjunction, allowing for more personalised management, as the specific drugs and risk-reduction measures provided for the purpose are reserved solely for those individuals exposed to the highest (clinical and genetic) risks (Nat Rev Genet 2018; 19:581-590;).

In practice, common diseases such as coronary heart disease, atrial fibrillation, sudden death due to cardiac arrhythmia and metabolic diseases (e.g. type 2 diabetes) are all considered for such an analysis.

Our teams and genetics, bioinformatics and technology specialists are at your disposal to discuss them.

The best example to illustrate the clinical application of PRS concerns breast cancer.

A PRS based on 313 SNPs has been validated to detect hormonal breast cancer (ER+) (Am J Hum Genet 2019; 104:21-34), which is the most common type of breast cancer (Nat Rev Dis Primers 2019; 5:66). Clinical risk factors are also examined using EC-approved CanRisk software, the most important two factors being breast density (ACR c-d) and body mass index (>25; Genet Med 2019; 21:1708-1718).

This software makes it possible to determine personal risk and then appropriate follow-up imaging for women at risk between the ages of 40 and 50. This is not currently the case, as only women at average risk receive mammograms between the ages of 50 and 74, whereas the monitoring of this younger segment of the population at higher risk, has the same sort of effect in terms of reducing mortality as the programme currently in place (Ann Intern Med 2016; 164:215-225).

PRS making it possible to calculate the risk of other cancers, e.g. prostate cancer or benign prostate hyperplasia, is currently being developed.

Our teams are at your disposal to advise or screen your patients.

Polygenic Risk Score (PRS) at Genesupport