Paternity testing allowing for uncertain mutation rates

This article discusses the use of probabilistic reasoning to analyse a disputed paternity case, where the DNA genotypes are compatible on all markers but one, allowing for the possibility of mutation, when the mutation rate is itself uncertain. It first describes the construction and Bayesian analysis of a suitable model for paternity testing, taking into account the potentially misleading effect of genetic mutation and allowing for mutation rate uncertainty, before introducing the simplest type of disputed paternity case. It then considers a specific disputed paternity case, in which an apparent exclusion at a single marker could indicate either non-paternity or mutation, as well as the features of the mutation process that need to be accounted for in the analysis. The results of a simple analysis of the specific disputed paternity case are examined and the analysis is set in the broader context of DNA profiling and forensic genetics.