A joint test of multiple genes can maintain weak control of FWER and should reveal greater evidence for association from a set of genes, although perhaps with less specificity for individual genes. This argument motivates the partial sum statistics [30], which are formed by obtaining test statistics (typically χ2 tests from a contingency table) for each individual gene and then forming the sum of the K largest statistics, where K is a fixed number called the length. The significance of the sum can be assessed by a permutation test and an overall significance estimated over a range of lengths.
