Mendel's pea trial, resulted in the law of segregation and law of independent assortment, then based the foundation of genetics. Thomas H. Morgan's law of linkage and crossing-over is no doubt a milestone of modern genetics. Genetics is gradually developed from macroworld to microworld, from superficial level to molecular level following the new findings from scientists. The complete of whole human genome sequencing in 2002 marked the new era of genetics, i.e. functional genomics times. Molecular markers pl...