Estimating Heritability of Different Types of Cancer

Isabella Locatelli, Università degli Studi di Torino
Andreas Wienke, Martin-Luther-University Halle-Wittenberg
Paul Lichtenstein, Karolinska Institutet

The aim of this study is to investigate the role of genes and environment in the susceptibility towards breast, prostate and colon cancer and to compare the estimates of heritability in the propensity to develop these diseases. We apply an interdisciplinary approach merging models developed in the field of demography and survival analysis – so-called frailty models – and models coming from the quantitative genetics and epidemiology, namely genetic models. This approach is applied to cancer data coming from the Swedish Twin Registry. The genetic-environmental decomposition of the cancer propensity is obtained in two steps. First, we apply a correlated frailty model in order to obtain an estimate of the population heterogeneity (frailty) in the susceptibility towards the disease and of the correlation between individual propensities within a twin pair. Second, different genetic models are compared in order to decompose the frailty variance into its genetic and environmental components.