In Re Fisher 421 F.3d 1365 (Fed. Cir. 2005) Figure 1: DNA Table 1: DNA base pairs DNA RNA A-T A-U G-C G-C

DNA, or deoxyribonucleic acid, uses nucleotide molecules of A (adenine), G (guanine), C (cytosine), and T (thymine) to make up its structure. As seen in table 1, A molecules pairs with T molecules and G pairs with C. These sets are called “base pairs.” RNA, or ribonucleic acid, substitutes U (uracil) for T (thymine).

Figure 1 depicts molecular DNA with the linked base pairs and the hydrogen bonds between them.

Figure 2: Protein Synthesis

Protein synthesis occurs through the process of transcription and translation. (Figure 2) The first step is through replication of DNA. DNA is then transcribed into messenger RNA or mRNA. After, mRNA can then translate into a protein using a ribosome, or it can produce complementary DNA, cDNA, through reverse transcription.

EST’s are short nucleotide sequences that are created by sequencing either ends of a strand of cDNA.

5’ cDNA 3’ A T T A A C G C T A T C C A T T G G A T T G C A A T G C C G T T A T T A A T T G C C G G C A A T A

3’ EST 5’ 3’ EST 5’ EST strands can attach to the original DNA to help with sequencing the genome, can attach to mRNA to determine if the mRNA is present and the amount, and can identify when mutations of the DNA occur called “polymorphisms.”

Fischer essentially wanted to patent small strands of sequenced DNA which were created from the maize plant DNA. These small EST strands would be the maize DNA verbatim. While EST’s do not naturally occur, the sequence of the EST does exist within the DNA of the maize plant.