Our major research interest is to look for functional human genetic variations and to understand their biological mechanism and evolutionary roles. Genetically, People differ from each other by hundred thousands of small genetic variations. A small fraction of these genetic variations affect function. They make us a phenotypically very diverse species. Such phenotype diversity occurs among populations, such as skin pigmentation and lactose tolerance in adulthood etc.; and also between individuals, such as stature, weight, psychological tendency and drug metabolism. To understand these functional genetic variations, two strategies are to be applied. The first is to detect and characterize evidences of positive selection. The second strategy is to use association related approaches.