Table 3. Cost comparison of four different methods of synthesizing the vip3aI gene using 60 or 90 nt oligonucleotides.

Length of oligos	60 nt	90 nt
Two-step successive PCR method
Number of oligos	60 (oligoA )	34 (oligoB)
Number of overlaps (bases)	1180	660
Total chemical syntheses (bases)	3562	3032
Unit price (USD)	0.20	0.70
Total price (USD)	712.4	2122.4
Single-step successive PCR method
Number of oligos	59 (oligoC )	34 (oligoD)
Number of overlaps (bases)	1160	660
Total chemical syntheses (bases)	3542	3042
Unit price (USD)	0.20	0.70
Total price (USD)	708.4	2129.4
PTDS method
Number of oligos	60 (oligoE )	34 (oligoF )
Number of overlaps (bases)	1180	640
Total chemical syntheses (bases)	3562	3022
Unit price (USD)	0.20	0.70
Total prices (USD)	712.4	2115.4
Single-step overlap extension PCR method
Number of oligos	60 (oligoE )	34 (oligoF )
Number of overlaps (bases)	1180	640
Total chemical syntheses (bases)	3562	3022
Unit price (USD)	0.20	0.70
Total prices (USD)	712.4	2115.4