Nonparametric versus Parametric Statistical Approaches for Genetic Anticipation: The Pancreatic Cancer Case

2000 Mathematics Subject Classi cation: 62N01, 62N05, 62P10, 92D10, 92D30.

Genetic anticipation for a particular disease can involve an earlier age of onset, greater severity, and/or a higher number of affected individuals in successive generations within a family. Comparison between nonparametric and semiparametric tests is studied for matched data, and is one of the main focuses of this study. This comparison is investigated for the variable age of diagnosis among different birth cohorts, before and after adjustment for time under observation. The comparison is illustrated on an example of familial pancreatic cancer, which example is the second main focus of this study. The nonparametric test performed on our example better than the two semi-parametric tests, and was less sensitive to right censoring. After adjusting for follow up time, all methods detected genetic anticipation.

This work was supported in part by a grant from the National Cancer Institute (1 R33 CA10595-01A2) to S. A. Sherman. G. R. Haynatzki thanks Mr. Oleg Shats and Mrs. Marsha Ketcham for their help with the PCCR.