In this webinar the genetic architecture and the clinical markers of cancer predisposition will be discussed. Susceptibility to cancer varies across individuals and is dependent on genetic factors. It is estimated that, overall, genetic factors account for about 37% of the total burden of cancer within a population. These genetic factors are associated with different magnitudes of risk: from very high (up to 100%) to low (i.e. < 0.1% increase over the general population risk). Currently, effective preventative measures can be undertaken only for carriers of genetic variants associated with high risk conditions, which overall account for 5-10% of all cancers.