PCR产物中无错误碱基拷贝最低比率的计算

The Calculation of the Minimum of Non-Base-Mismatch Copy Proportion of the PCR Pro-ducts.

分析了ＰＣＲ过程中带有错误碱基拷贝的量变过程，得出不同循环（ｎ）后不同类型拷贝数的计算通式并以逐次代入方式归纳出ＰＣＲ产物中无错误碱基拷贝最低比率（Ｒ）和有效循环数（Ｎ），拷贝酶促合成链长（Ｈ）及错配率（ｆ）的关系式Ｒ＿ｎ＝（１－Ｈｆ／２）￣（Ｎ－１）（１－Ｈｆ），对ＰＣＲ技术制备表达用ＤＮＡ片段有指导意义．

The quantity change of the copieswith mismatch bases in PCR products wasanalyzed.The general formulas of numbers ofcopies in different modes after certain cycles(n)were gained and the math relation betweenthe minimum(R_n)of the non-base-mismatchcopy proportion of PCR products and the effi-ciency cycle numbers(N),the copy chainlength(H)catalyzed by Taq polymerase andthe mismatch frequency(f)was concluded byway of substituting step by step:R_n=(1-Hf/2)￣(N-1)(1-Hf).The formula has a guid-ance sense for preparing the gene segmentsused for the gene expression by PCR tech-nique.