Scientists crack genetic code of mice to aid Man

The mouse has become the latest living organism to have its genetic code unravelled, in a scientific breakthrough that promises to provide new insights into human diseases.

The mouse has become the latest living organism to have its genetic code unravelled, in a scientific breakthrough that promises to provide new insights into human diseases.

Scientists announced yesterday the completion of 96 per cent of the mouse genome – its genetic blueprint – and are heralding the achievement as a milestone in the understanding of human genetics.

The mouse is considered important because it has become the most ubiquitous animal used in biomedical research. It also shares many of its genes with man, making it an excellent model to study human illnesses.

An international team of scientists, including ones from the Sanger Institute near Cambridge, published the draft sequence of the mouse genome on the internet. "This information will allow researchers to gain insights into the function of many human genes because the mouse carries virtually the same set of genes as the human but can be used in lab research," said a statement from the Sanger, the Whitehead Institute in New York and Washington University in St Louis, Missouri.

"For most human illnesses, from cancer to auto-immune disease, important insights have come from the study of mouse models. Having this advanced draft of the mouse sequence will greatly accelerate precise identification of the genetic contributors to those illnesses, leading to better understanding of human diseases and improved treatments."

A preliminary comparison of the genomes of mice and men reveals they share roughly the same number of genes – about 30,000 – although the mouse genome is 15 per cent smaller and has only 20 pairs of chromosomes compared with the 23 pairs of human chromosomes.

Mice and men had a com-mon ancestor 100 million years ago, when dinosaurs were the dominant land animals, which was why they shared many of their most important genes, Eric Lander, director of the Centre for Genome Research at the Whitehead Institute, said. "The mouse genome provides an important chapter from evolution's lab notebook. Being able to read evolution's notebook and compare genomic information across species will allow us to glean important information about ourselves.

"Evolution preserves the most important genetic information across species. If specific DNA sequences have been preserved by evolution over hundreds of millions of years, they must be functionally important."

The international Mouse Genome Sequencing Consortium, funded by Britain's Wellcome Trust and the Medical Research Council, said the correct position of every genetic "letter" in the DNA of the mouse was determined at least seven times to ensure accuracy.

"The quality of the working draft sequence far exceeds the consortium's original expectations for this stage and was completed much sooner than initially expected, reflecting the tremendous efficiencies gained in sequencing and computational technologies in the past few years," a spokesman for the consortium said.

"The sequence information is immediately and freely available. The information will be utilised thousand of times daily by science and industry, as well as by commercial database companies providing information to biotechnologists."