肤色是最为显著的人类性状之一，具有广泛的族群差异，多项研究显示遗传率可高达0.7~0.9。目前虽已较为清楚肤色形成的生理基础和分子生物学机制，发现了一批受定向选择影响的肤色相关遗传多态位点，但形成肤色多样性的深层次进化遗传学机制和原理仍未阐明。本项目充分发挥课题组在群体与进化遗传学研究中的优势，探索人类肤色多样性背后的深层次进化遗传学机制和原理，在已有坚实研究基础上，重点开展以下研究工作：人类迁徙过程中肤色相关基因进化压力动态变化的定量研究；多基因遗传相互作用在肤色多样性形成中的作用和意义；混合群体中个体肤色性状差异对遗传交流的影响；选择压力下遗传位点间连锁不平衡的衰退规律等。以上研究，不仅可进一步揭示肤色多样性形成的遗传和进化原理，更重要的是以现代人类迁徙中肤色相关基因的进化过程为例深化对人类复杂性状形成过程的理解，在分析大量实际数据的基础上总结出遗传进化规律，丰富和完善人类遗传学理论。

Skin color is one of the most significant human traits with a very high diversity among worldwide populations. Studies shows that its heritability may as high as 0.7~0.9. After years of unremitting efforts, the researchers have made a clearer understanding of the physiological basis and molecular biological mechanism of formation of skin color. Many genetic polymorphisms contributed to diversifying skin colors are identified with significant signatures of directional selection. However, our understanding to driving forces of the genetic diversity of human skin color is still limited and we cannot thoroughly understand the underlying genetic principles. In this proposal, our team gives a full play to the advance of population and evolutionary genetics and explore the principles of the genetic diversity. Based on our achievements in the past years, our group will focus on the following issues: Quantitative study on the dynamics of evolution pressure changes of color-related genes during human migration; the role and significance of multi-gene genetic interaction in the formation of skin color diversity; the influence of individual color differences on genetic exchange in mixed population; degeneration of linkage disequilibrium in the presence of environmental adaption or sexual selection. In this project, the exploration on the above issues can not only further reveal the genetic and evolutionary principles of the formation of skin color diversity, but also take the evolution of the involved genes as an example to deepen the understanding of the human complex traits. Based on empirical data, we will discove rules in genetics of human skin color and try to expand our understanding in human genetics.