Recently-developed genotype imputation methods are a powerful tool for
detecting untyped genetic variants that affect disease susceptibility in
genetic association studies. However, existing imputation methods require
individual-level genotype data, whereas, in practice, it is often the case that
only summary data are available. For example, this may occur because, for
reasons of privacy or politics, only summary data are made available to the
research community at large; or because only summary data are collected, as in
DNA pooling experiments.