1. Center for Computational Biology College of Biological Sciences and Technology Beijing Forestry University Beijing 100083 China
2. Yuanpeng Genome Institute of Jiangsu Nantong Jiangsu 226531 China
3. The Nurturing Station for the State Key Laboratory of Subtropical Silviculture Zhejiang Agricultural and Forestry University Lin'an Zhejiang 311300 China
4. Center for Statistical Genetics The Pennsylvania State University Hershey PA 17033 USA