本世纪七十年代开始,国外一些科学家相继报道了有关使用不同的染色方法得到的G带,C带和Q带的染色体变异体(chro-mosome variats)或称染色体多态性。(chromosome polymorphism)。后经研究发现,在个体上个体之间,某些染色体片段的存在与否,可以不同。或者这些染色体片 Since the seventies of this century, some scientists abroad have successively reported chro-mosome variats or chromosome polymorphisms about G, C and Q bands obtained by different staining methods. (chromosome polymorphism). After the study found that individuals in the individual, the presence of certain chromosome fragments can be different. Or these chromosome pieces