Dorsa

Dolly the sheep was the first mammal to be cloned from an adult somatic cell, using the process of somatic cell nuclear transfer (SCNT). She was born on July 5, 1996, at the Roslin Institute in Scotland, and her creation marked a significant milestone in the field of genetic engineering and biotechnology.

Background

The cloning of Dolly was a result of research conducted by a team led by Ian Wilmut and Keith Campbell at the Roslin Institute. The primary goal of their research was to develop a method for producing genetically modified livestock. Dolly's creation demonstrated that it was possible to take a fully differentiated adult cell and reprogram it to develop into a new organism.

Cloning Process

The process used to create Dolly is known as somatic cell nuclear transfer (SCNT). This involves several key steps:

1. A donor cell is taken from the adult organism to be cloned. In Dolly's case, this was a mammary gland cell from a six-year-old Finn Dorset sheep.
2. The nucleus, which contains the genetic material, is removed from the donor cell.
3. An egg cell is taken from a different sheep, and its nucleus is removed, creating an enucleated egg.
4. The nucleus from the donor cell is inserted into the enucleated egg.
5. The egg is stimulated to begin dividing and developing into an embryo.
6. The embryo is implanted into a surrogate mother sheep, where it develops until birth.

Dolly was the only successful live birth from 277 attempts, highlighting the challenges and inefficiencies of the cloning process at the time.

Significance

Dolly's birth was a groundbreaking achievement in the field of genetic engineering. It proved that it was possible to clone a mammal from an adult somatic cell, which had significant implications for reproductive cloning, therapeutic cloning, and stem cell research.

Dolly's creation raised ethical and scientific questions about the potential for human cloning, the welfare of cloned animals, and the implications of cloning technology on biodiversity and conservation.

Health and Legacy

Dolly lived for six and a half years, during which she gave birth to six lambs. She was euthanized on February 14, 2003, due to a progressive lung disease and severe arthritis. Her relatively short lifespan and health issues raised questions about the long-term viability and health of cloned animals.

Dolly's legacy continues to influence research in genetics, biotechnology, and bioethics. Her remains are preserved and displayed at the National Museum of Scotland.

Also see

• Cloning
• Genetic engineering
• Stem cell research
• Bioethics
• Roslin Institute