The KanGO project is using the DNA of the tammar wallaby (Macropus eugenii) as its chosen representative of the kangaroo family. It is the first Australian marsupial to be sequenced.
Credit: ANU
SYDNEY: Australian scientists have today launched a map of the kangaroo genome. This is the first and most important stage in their quest to discover the genetic sequence of the iconic marsupial.
"A good map is crucial for finding our way around a new genome," said geneticist and director of the project Jenny Graves, who divides her time between the Australian National University in Canberra and the University of Melbourne.
A complex puzzle
"It enables us to explore how the genomes of mammals - including humans - are organised, how they functions, and how they evolved," she said.
The detailed genome map is the most difficult part of the sequencing method, said Graves. Because a chromosome can't be sequenced from top to bottom in one go, it has to be cut into smaller, workable pieces.
Specific points on the chromosome must then be mapped out so that all the pieces can be put back together again in the right order.
The map has taken researchers at the ARC Centre of Excellence for Kangaroo Genomics (KanGO), based at a number of universities, around five years to complete.
But progress should be faster moving forward, and the complete sequence is due to be published next year.
Human development clues
Graves said the team are focussing on the kangaroo's X chromosome, as well as its fifth chromosome which has similarities to sections of genes on the human X chromosome.
Essentially humans and kangaroos have the same set of 20,000 genes, said Graves, but the differences lie in the sequences of those genes and when in development they are turned on and off.
"Kangaroos are a marvellous model for studying human development and reproduction because they are born very early and complete much of their development in the pouch – rather than the womb," said the University of Melbourne's Marilyn Renfree who is taking over as KanGO director from today.
"This makes them a powerful tool for studying the genes and hormones involved in mammalian reproduction and development," she added.
The power of differences
Part of the race to sequence the genomes of a variety of mammals and other animals is driven by the value of comparing genomes, particularly the genomes of distantly related species, to reveal hidden details about the human genome.
Frank Grützner, a University of Adelaide geneticist who worked on the recent platypus genome sequence, said that the completion of the first phase of the kangaroo genome "highlights what a treasure trove Australia is for studying isolated genetic material."
The first marsupial genome to be published was the American opossum in 2007. Last year an international team including Australians released the platypus genome, the first monotreme to be sequenced (see, The platypus unravelled, Cosmos Online).
The KanGO project is using the DNA of the tammar wallaby (Macropus eugenii) as its chosen representative of the kangaroo family, it is the first Australian marsupial to be sequenced.
