Title:?Efficient phylogeny based genome-wide association mapping method. Abstract: The goal of genome wide association (GWA) mapping in modern genetics is to identify genes or narrow regions in the genome which contribute to genetically complex phenotypes such as morphology or disease. Existing methods include single-marker, haplotype and phylogeny-based association mapping. Phylogeny-based association mapping utilizes phylogenetic trees which are rich yet compact representations of the genetic relationships between samples. Thus phylogeny-based methods show obvious advantages over single marker-based and haplotype-based methods by incorporating richer information of the evolutionary history. However, most of the existing phylogeny-based methods are time-consuming and not scalable to genome-wide analysis. I developed two efficient phylogeny-based association mapping methods, TreeQA and TreeQA+, which utilize local perfect phylogenies constructed in genomic regions exhibiting no evidence of historical recombination. TreeQA is highly efficient because it uses linear-time algorithm to construct local perfect phylogeny trees, conducts effective permutation tests and maximizes the reuse of intermediate computation. Moreover, TreeQA is more robust and effective than previous phylogeny-based methods due to its ability to remove outliers induced by the tree topology and search for associations in sample subspaces. TreeQA+ inherits all advantages of TreeQA. Moreover, it improves TreeQA by utilizing the Brownian motion and maximum likelihood model to incorporate sample correlations induced by the topology of the phylogenetic trees (The correlations violate the sample independence assumption and are ignored by previous association methods.). The method is also extended and applied to association analysis in high dimensional data of any domains, which is a general data mining problem.