{TAIL ~ Incorporation} of {HEAD ~ the analog} is expressed as a percent of incorporation of the complementary deoxynucleotide 
{ TAIL ~ Incorporation } of { HEAD ~ the analog } is expressed as a percent of incorporation of the complementary deoxynucleotide
TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH