Dideoxy chain termination.
<P>
   A DNA fragment is denatured to produce a single-stranded template in a
   PCR reaction with the following:
<P>
<BR><LI> DNA primer
<BR><LI> DNA polymerase
<BR><LI> the four different deoxyribonucleotides (dNTPs)
<BR><LI> four different dideoxyribonucleotides (ddNTPs)
<P>
   continue