These regions of DNA are amplified through PCR and separated by size through the process of .

Gel electrophoresis

Explanation:

Gel electrophoresis allows for the separation of nucleic acid molecules are  by applying an electric current through a matrix of agarose. This electric field moves the negatively charged molecules down the gel.

Shorter molecules move faster and migrate farther down the gel than longer molecules, because the smaller molecules migrate more easily through the pores of the gel. These properties allow fragments of DNA to be separated by size.