Megan and Morag facts for kids

Megan and Morag were two domestic sheep. They were the first mammals successfully cloned from special cells called "differentiated cells." It's important not to confuse them with Dolly the sheep, who was the first animal cloned from an adult cell. Also, they are different from Polly the sheep, who was the first cloned animal that also had new genes added (transgenic).

Megan and Morag, just like Dolly and Polly, were cloned at the Roslin Institute in Edinburgh, Scotland. This happened in 1995.

How They Were Cloned

Scientists at the Roslin Institute wanted to find a better way to change the genes of sheep and cattle. Before, they used a method called microinjection. This involved injecting DNA into a fertilized egg. However, this method was not very precise. Only a few animals would actually use the new DNA, and even then, the new genes didn't always work as expected.

A New Approach

The team decided to try a new method. They combined microinjection with the idea of using embryonic stem cells. Their goal was to move the nucleus (which holds the DNA) from one cell into another. Then, they would try to make this new cell grow into a whole animal. This process is called nuclear transfer.

The scientists first tried to create special "stem cell" lines from sheep embryos. These cells can turn into any type of cell in the body. But they didn't succeed with that. So, they decided to work with cells taken from a very early stage of development called a blastocyst.

The Cloning Process

Here's how they did it:

• They took the nucleus from a blastocyst cell.
• They put this nucleus into an unfertilized sheep egg cell. The original nucleus of the egg had been removed.
• To help the process work better, they put the blastocyst cells into a resting state. This made them similar to the unfertilized egg cell.

The nuclear transfer was done using electricity. The electricity helped the blastocyst cell and the egg cell join together. It also helped start the development of the new embryo.

The Birth of Megan and Morag

The scientists performed 244 nuclear transfers. Out of these, 34 embryos grew enough to be placed into surrogate mothers (sheep that would carry the babies). In the summer of 1995, five lambs were born. Two of these lambs, Megan and Morag, grew up to be healthy adult sheep that could have their own babies.

These two sheep were very important. They were the first mammals ever cloned from differentiated cells. They were born in June 1995 and were given the names 5LL2 and 5LL5.

The birth of Megan and Morag showed that it was possible to clone sheep using cells grown in a lab. Their success was a big step forward. It made the cloning of Dolly the sheep possible a year later. Even though Megan and Morag were born first and were very important, they didn't get as much attention as Dolly. In 2005, Megan was still alive and was the oldest cloned animal at that time.

See also

• List of cloned animals