Every child inherits 50% of their DNA from each of their two biological parents. However, each child’s genome actually contains a few genetic variants that are not present in either of their parents’ genomes. These genetic variants are called mutations, and they occur because DNA sometimes gets damaged or mis-copied when it gets passed down from parents to children. The aim of our research project is to figure out why some children might be born with more mutations than others, and to study what the mutation rate might generally mean for their health and their families’ health. In particular, we will test the hypothesis that a higher mutation rate might be linked to cancer, infertility, or shorter lifespans.