How to Make and Use a DNA Fragment Standard Curve

How to Make and Use a DNA Fragment Standard Curve

Purpose of the DNA Standard Curve To determine the fragment sizes (base pairs) in an unknown sample The marker/ladder (control) is used to prepare a standard curve Provides a standard for comparison to the unknown fragment sizes Known as called "interpolation

How are Standard Curves Created? Begin with a set of standards of a known quantity Relate this known quantity to something we can measure Graph the relationship to create a standard curve Determine size of an unknown DNA fragment

bottom ____ edge of the well. the bottom

A picture of the gel is taken and used to make the measurements bottom edge

bottom edge

Start with the smallest fragment and continue to plot the larger fragment sizes until all are plotted. Draw a best fit line through the center of the points.

Do not draw a line through each point.

“interpolation”