Fruit flies, UA creating buzz in study of genetics

November 13, 2007

By hammersmith

[Source: ALAN FISCHER, Tucson Citizen] – UA researcher Therese Ann Markow appreciates the huge role that fruit flies, the tiny pests that buzz around decaying fruits and vegetables, have played in the study of genetics.

But she still smashes them when they hover around her glass of wine.

“Even though many people think of them just as flies, I think they are a great opportunity to learn many things that can ultimately benefit people,” she said.

Markow, a University of Arizona regents’ professor of ecology and evolutionary biology, is a corresponding author of a paper published Wednesday in Nature comparing the evolution of the genomes of 12 closely related fruit fly species.

Markow, a member of the UA BIO5 Institute, led a team that selected and provided the DNA for eight of the 12 species of Drosophila – the fruit fly – that will be used to study how genes and genomes have evolved in the tiny critters.

The four-year process involved inbreeding thousands of flies over eight to 14 generations to develop clean lines with no genetic variations.

The DNA was harvested from fly embryos so it would not be contaminated by the bacteria and yeast the insects eat, she said.

Sequencing, which was done elsewhere, is the process of determining the arrangement of the components that make up the genetic material.

The 12 species studied come from different ecological backgrounds and histories, she said.

The species’ genomes evolved between 1 million and 40 million years ago, which offers researchers a good look at how the flies changed over time.

“We can ask about the tempo and mode of genome change because we have species that diverged varying amounts of time ago,” she said.

And flies from the desert evolved differently than flies living in the tropics, she said.
Researchers can look at how the fly’s genes developed ways to deal with heat, lack of water, environmental poisons, invasive species and other threats.

“Applications for this are very far reaching,” she said.

Human applications could include looking at detoxification, adapting to stresses, resistance to toxins, utilizing different kinds of resources, and understanding metabolism as it relates to diabetes research, she said.

While the fruit flies breed in decaying material and are often found around rotting fruit and vegetables, they play a vital role in scientific research, she said.

“They are hugely valuable flies. They all have different stories to tell,” she said.

“They are the organism by which many genetic principles have been discovered. They are historically very valuable.”