Question

1. Describe two ways in which transgenic animals are used in medicine today.

2. Explain how the following transgenic crops are different from the traditional crops:
   1. Bt Corn:
   2. Flavor Savor Tomato:

Answer 1

there are many advantages of transgenic animals in medicine.

some transgenic animals are produced as disease models so that the researchers could study the effects and would be able to develop diagnostic and therapeutic strategies. for example, Harvard scientists were able to create a transgenic mouse called Oncomouse or Harvard which carried a gene that promotes various human cancers. this mouse has been patented too.

xenotransplantation
around the globe, several patients die every year due to lack of replacement organs such as heart, liver, or kidney. Transgenic pigs were developed to provide transplant organs. however, the possibilities for transplantation are still being studied since xenotransplantation is hampered by a pig protein that would cause donor rejection. research is being extensively carried out to remove the pig protein and replace it with a human protein.

pharmaceuticals
Diabetes is a major problem affecting a huge number of people. insulin injections are needed for such diabetic patients in later stages. though insulin is available in the market in several forms, many people are not able to afford due to the high cost. Products such as insulin, growth hormone, and blood anti-clotting factors may be obtained from the milk of transgenic cows, sheep, or goats.

nutritional supplements

The first transgenic cow, Rosie, in 1997, produced human protein-enriched milk at 2.4 grams per liter. This milk is a more nutritionally balanced product than natural milk and could be fed to babies or the elderly with special nutritional or digestive needs. Rosie’s milk contains the human gene alpha-lactalbumin.

human gene therapy
Transgenic animals could play a major role in treating genetic disorders where a prominent cure is not yet available. For example, a transgenic calf was produced in Finland with a gene that makes the substance that promotes the growth of red cells in humans.

Bt cotton contains cry gene which produces insecticide against lepidopteran insects. this eliminates the use of insecticide on the plants since the transgenic plants have the inbuilt defense mechanism against the insects.

Flavr savr tomatoes are genetically modified tomatoes where the ripening process is slowed down to prevent it from softening. it contains an antisense gene that interferes with the production of the enzyme polygalacturonase, which degrades pectin in the cell wall and causes softening.