The genome is all the DNA making a particular living cell or whole organism.  Read more here.

Sequencing a genome to find out the order of bases of nucleotides in the genes of the DNA is a very time consuming and expensive project. 

The human genome project was completed in 2003 and cost 3 billion dollars!

At only 1 million dollars, the mammoth genome project is relatively cheap!

Genes allowing mammoths to develop ways to survive in very cold climates, such as growing woolly hair, can now be identified.

Comparing the differences between the DNA of mammoths found in permafrost in different parts of the world should enable scientists to understand how and when they split from the ancestors of our modern elephants.

Read more about mammoths here.

But don't expect any revival of mammoths by cloning in the near future - although the sequence of their genes has been found, nobody knows how those genes were organised into chromosomes.  And with 400,000 differences in the genes compared to elephants, it is not feasible to change an elephant's genes one at a time to resemble those of mammoths.

Read this article in Greek