How to minimize DNA degradation?

A) 可能是DNA提取过程中混合太剧烈；B) 跑胶液用的次数太多; C) 材料本身多糖太多影响DNA酶抑制剂的作用; DNA 保存不当。

A) Mixing too vigorously during the DNA isolation; B) Electrophoresis buffer too old; C) Staring bio-sample contained high amount polysaccharides; D) DNA sample was not stored properly.