Genetic Engineering: Moving a Gene into Another Organism

0:00How can bacteria make human insulin, a medicine for people with diabetes?

0:06A gene is a section of DNA with the instructions for one protein, like insulin.

0:12Genetic engineering moves a gene from one organism into another.

0:17First, a restriction enzyme, which cuts DNA at a particular sequence, cuts the gene out.

0:24Bacteria also carry plasmids, small rings of DNA separate from their main DNA.

0:31The same enzyme cuts a plasmid open, so its ends match the ends of the gene.

0:37The gene fits into the gap, and an enzyme called ligase joins the ends.

0:42The plasmid goes into a bacterium, which divides: one becomes two, then four, then eight.

0:50Each one uses the gene to make human insulin, a medicine for diabetes since 1982.

0:57Corn given a gene from a soil bacterium makes its own insecticide, a protein that kills some insect pests.

1:05A common myth: GM, or genetically modified, food has genes and other food does not.

1:12In fact, any food made of cells has genes. GM food just has a few genes added or changed.

1:20Newer tools such as CRISPR can edit a chosen gene more precisely.

1:25Possible benefits: medicines like insulin, crops that resist pests, and bigger harvests.

1:33People weigh these against concerns: effects on wildlife, long-term safety, and who owns the seeds.

1:41Genetic engineering moves a gene into another organism, which then makes the same protein.