TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Minichromosome: The minichromosome further comprises a telomere and an autonomous 15 replicating sequence. The minichromosome further comprises a structural gene, e.g. a selectable or screenable marker gene, an antibiotic resistance gene, a ligand gene, an enzyme gene, a herbicide resistance gene, a nitrogen fixation gene, a plant pathogen defense gene, a plant stress-induced gene, a toxin gene, a receptor gene, a gene encoding an enzyme, a gene encoding an antibody, a gene encoding an antigen for a vaccine, a transcription factor, a cytoskeletal protein, a DNA-binding protein, a protease, an endonuclease, a lipid, a seed storage gene, an interleukin gene, a clotting factor gene, a cytokine gene, a growth factor gene and a biosynthetic gene for producing pharmaceutically active proteins, small molecules with medicinal properties, chemicals with industrial utility, nutraceuticals, carbohydrates, RNAs, lipids, fuels, dyes, pigments, vitamins, scents, flavors, vaccines, antibodies, or hormones. The minichromosome is capable of expressing the desired structural gene. Preferred Transgenic Crop: The crop is a dicotyledonous plant, e.g. tobacco, tomato, potato, sugar beet, pea, carrot, cauliflower, broccoli, soybean, canola, sunflower, alfalfa, or cotton. The crop is a monocotyledonous plant, e.g. wheat, maize, rye, rice, turf grass, oat, barley, sorghum, millet, or sugarcane. EXAMPLE - A minichromosome can be maintained in E. coli or other bacterial cells as a circular molecule by placing a removable stuffer fragment between the telomeric sequence blocks. The linear minichromosome was isolated by, for example, gel electrophoresis. The minichromosome contained replication origin and selectable marker that can function in plants to allow the circular molecules to be maintained in bacterial cells. The minichromosomes also included a plant selectable marker, a plant centromere, and a plant ARS to allow replication and maintenance of the DNA molecules in plant cells. Finally, the minichromosome included several unique restriction sites where additional DNA sequence inserts can be cloned.