UF expert: redesigned DNA points to future for "personalized" medicine

October 21, 2004

GAINESVILLE, Fla. — Fifty years after James Watson and Francis Crick discovered DNA’s structure, scientists are learning to redesign it, creating new ways to diagnose diseases and unlocking the chemical ancestors of life, a University of Florida chemist writes in a paper to appear in this week’s issue of the journal Science.

“This is a great opportunity for research,” said Steven Benner, a UF distinguished professor who was invited to write the paper. “When they introduced DNA’s structure, it was obviously correct, and everybody said, ‘Oh, of course, that’s how it has to be.’ But if you look at it closely, it doesn’t have to be that way.”

DNA is a ladder-shaped molecule, a double helix composed of two entwined strands connected by many rungs, or pairs, of amino acid bases. The bases are arranged in an order that determines the genetic instructions for the development of all forms of life.

Manipulating the structure of DNA has created a new field of synthetic biology, Benner said. Scientists are tinkering with everything from the ribose sugar backbone to the base pair rungs in an effort to develop new ways to diagnose diseases such as HIV, SARS and cystic fibrosis.

Scientists also want to know why DNA has the structure it does and how it formed in Earth’s earliest days. They now may have part of the answer: Recent research suggests that minerals present in the ancient deserts of the early Earth may be necessary to stabilize the backbone of the DNA molecule, Benner said.

The future of redesigned genetics will include individually tailored patient care, or “personalized” medicine, Benner said.

“These kinds of technology are going allow you to sequence your genome cheaply. A lot of how patients react to a drug is genetically determined,” he said. “We need to be able to go in and profile you as a patient and decide what medication you’re going to do well with and what you’re not going to do well with.”

One possible result of this genetic mapping is that drugs the FDA has shelved because of adverse reactions in small percentages of patients may eventually be made available to patients who have no genetic predisposition to side effects from these drugs.

While it costs $10 million to sequence a single human genome today, practical personalized medicine would require reducing that figure to $10,000. Though its potential benefits are evident, inexpensive human genome sequencing may be years away.

“It’s hard to predict the future when you have this combination of science, technology, economics and, of course, social issues,” he said. “But that’s the vision; that’s what we’re looking for.”

Benner can be reached by cell phone at (352) 219-3570 or by e-mail at benner@chem.ufl.edu.