According to the science, extinct species similar to mammoths could be brought back to life by cloning them.

Associate professor of ecology and evolutionary biology at the University of California, Santa Cruz, Beth Shapiro describes in her new book 'How to Clone a Mammoth'. Researchers said that there is no method to clone dinosaurs as their DNA is lost for good. But there is a possibility that something could be done with more recently-extinct species, like mammoths, passenger pigeons and the gastric-brooding frog.

In her new book, Prof. Shapiro explores that which species must be brought back, how to sequence their genomes, and how to expect which populations that have been overlooked in the wild, might be revived.

"I question if it's something we should do at all, for many ethical and environmental reasons. I'm trying to separate the science from the science fiction, because too much of what people hear is science fiction", said Prof. Shapiro.

Prof. Shapiro said that they could not able to clone a mammoth as geneticists have only recover fragments from frozen specimens. But, it is feasible to put in mammoth genes into a modern elephant's genome in order to create an animal with certain mammoth traits. An announcement has been made by geneticists at Harvard University in March that they inserted 14 Woolly Mammoth genes into the DNA of a live Asian Elephant.

Professor of genetics, George Church and the team of researchers studied mammoth DNA from very well preserved specimens that were gathered on Wrangel Island in the Arctic Ocean. The geneticists took help of a modern technique called clustered regularly interspaced short palindromic repeat (CRISPR). This enabled the researchers to edit DNA accurately.