However, in the mid-1990s the tools for reading the sequence of the genome were primitive. Data was scarce and expensive to generate, and a major early focus of the Human Genome Project was to develop better methods. In the meantime, one solution was to use genetics – how the genome is mixed and passed from one generation to the next – as a means of deriving more information from the available data. Siblings share half their genomes; but cousins one eighth, second cousins one thirty-second, etc. Studying patients linked by extended genealogies should therefore make it possible to more efficiently find the inherited component of any phenotype or trait, even using low-resolution markers.