Pufferfish could be key for humans


Scientists are turning to the pufferfish as the unlikely key to finding cures for human diseases.

Experts have just started working towards unlocking the genetic make-up of the fish as an important way of interpreting the human genome.

Compared to humans, the fish contains only a fraction of the genes, making it easier to understand because it is so basic. It means the sequence can be used to find the most important genes in humans and speed up new approaches to tackling disease.

Researchers are using technology and software developed during the race to decode the human genome and complete 95 per cent of the sequence by March of next year.

Dr Greg Elgar from the Sanger Centre in Hinxton near Cambridge said: 'The basic reason for using a pufferfish is that compared to the human genome it has around an eighth of the bases.

'But because it is a vertebrate it is pretty similar to the human genome and has less 'junk' DNA' which does not do anything.'

Completion of the human genome was announced in June. Scientists also hope to complete the DNA sequence of mice by early next year.

Dr Elgar said: 'A lot of effort has gone into sequencing the genome for the mouse because it is so similar to the human genome. The pufferfish genome is much further removed from humans so that gives two very useful comparisons.

'Sequencing human DNA is in itself only part of the job, you really need something to compare it with.'

The ability to compare the human DNA sequence with those of mice and pufferfish creates the equivalent of the Rosetta Stone - which carries the same inscription in different languages and allowed Egyptologists to decipher hieroglyphics.

The value of the pufferfish genome was first identified by Dr Sydney Brenner from the Medical Research Council's Human Genome Mapping Project in Cambridge 10 years ago.

However only a fraction of the fish's genome has been sequenced in that time as scientists looked at different genes on an adhoc basis.

Funding to decode the entire sequence has been provided by the American Government and is expected to cost in the region of US$200 million. The sequence will be decoded in America and made public to allow scientists throughout the world use the information for new medical research.

by Duncan Milner