Cloning Technology & Research

What is cloning?

Cloning is a number of different processes that can be used to produce genetically identical copies of a biological entity. The exact copy of the original genetic makeup is referred to as the clone.

Artificial Cloning

Gene Cloning

The three types of artificial cloning include: gene cloning, reproductive cloning, and therapeutic cloning.

Gene cloning, or DNA cloning, produces exact copies of segments of DNA or genes. This process includes inserting a gene from one organism into the genetic material of a carrier called a vector. The vector could include: bacteria, yeast cells, viruses, etc. The vector is placed in a lab conditions that cause it to multiply, resulting in the replication of the gene. -Genome

Reproductive Cloning

Reproductive cloning produces copies of whole animals or organisms. During this process, a somatic cell is removed from an animal. The DNA from the somatic cell is then transferred into an egg that has had its own DNA removed. There are two ways to add the DNA from the somatic cell to the empty egg.

  • Remove the DNA-containing nucleus of the somatic cell and inject it into the egg
  • Use an electrical current to fuse the somatic cell with the egg cell
The egg develops into an embryo and is implanted into the womb of an adult female animal. Reproductive cloning may require a surrogate mother to allow the development of the embryo. For example, Dolly the sheep required a surrogate mother. -Genome

Therapeutic Cloning

Therapeutic cloning produces embryo stem cells for the replacement of injured or diseased tissues. The stem cells created are used for understand disease and developing new treatments for disease. -Genome

Dolly the Sheep

Dolly the sheep, was the first mammal to be cloned from and adult cell. Dolly was cloned at the Roslin Institute in Scotland after 277 attempts. An udder cell from a six year old Finn Dorset white sheep was used to produce her. They injected the cell into an unfertilized egg cell that had no nucleus and fused the cells by using an electrical current. The cell was cultured for six- seven days to see if it divided normally before implanting it into a surrogate mother. The surrogate mother was a Scottish Blackface Ewe. From the 277 cell fusions, 29 early embryos developed and were implanted into 13 surrogate mothers. Dolly was born 148 days after she was implanted into the mother. -Science Daily
How they cloned Dolly the sheep.

What Are the Benefits of Cloning?

The U.S. Food & Drug Administration (FDA) decided that meat and milk from cloned animals were just as safe as those from non-cloned animals after consulting many scientists and experts in cloning. The FDA made it legal for researchers to use cloning for agricultural traits, such as milk production or lean meat. Another, up side to cloning is drug testing. Cloned animals used for drug testing are genetically identical, which means their response to the drugs should be similar to that of non-cloned animals. Some people have expressed the interest in having their deceased pets cloned in the hope of getting a similar animal to replace them. -Genome

What are the Drawbacks of Cloning?

Researchers have observed quite a few health effects in sheep and other mammals that have been cloned. These adverse effects include: increase in birth size and defects in vital organs, such as the liver, brain, or heart. This is caused by the shrinking of the tips of the chromosomes, or telomeres. The telomeres become so short that the cell can no longer divide and eventually the cell dies. Clones created from a cell that already has chromosomes that are shorter than normal may condemn the clones' cells to a shorter life span. For example, Dolly who was cloned from the cell of a 6 year old sheep, had shortened chromosomes thus why she died when she was 6 years old. -Genome