As the genomics revolution gathers pace, mathematicians have been enlisted to enable analysis of the gigabytes of data generated in gene sequencing.

Conrad Burden, of the Mathematical Sciences Institute and the John Curtin School of Medical Research at the Australian National University, is at the forefront of bioinformatics.

He is working on faster, more accurate mathematical algorithms to scrutinise genetic sequence data to work out the relationship between individuals or species. An ultimate application of these algorithms will be to aid in assembling the evolutionary "family tree" of life on earth.

The DNA blueprint is coded in the letters A, C, G and T, representing the chemical bases adenine, cytosine, guanine and thymine. In phylogenetics studies, scientists use computer programs to compare the sequences of different individuals by counting the differences in the order of the letters.

However, the usual method - lining up the sequences and comparing them - consumes huge amounts of computer run time, especially for big genomes. For example, the human genome of 20,000 genes has a blueprint of 3 billion pairs of letters.

Burden is working on an alternative method called k-word matching, that does not involve alignment of long sequences. It counts the number of matches between short "words" in the codes. "It simply counts the number of whole or partial word matches common to both sequences," says Burden. "We're counting lots of little stretches of DNA whereas the alignment method looks for one long run of letters."

Burden is drawing on statistical theory to validate the results by assessing whether they could be explained purely by chance. The method is expected to find applications in evolutionary genetics and studies of gene regulation - the process by which genes are switched on or off.

He says he was attracted to ANU by the opportunity to do interdisciplinary research.
"ANU has the whole gamut of specialists to collaborate with - medical researchers, biologists, mathematicians, chemists and physicists."

He says bioinformatics is an expanding field. "It's going to need more and more mathematicians."

Burden previously worked in subatomic particle physics but says mathematicians have the flexibility to apply their knowledge to many fields. "Once you have a basic, solid grounding in maths, you can apply it to other areas as well."