[Published in 'spoonful of medicine' a blog from Nature Medicine, January 9, 2013]
By Elie Dolgin – They may have wings, but fruit flies spend plenty of time on their feet. And these insects, also known as Drosophila, are a standard animal model for studying neurodegenerative diseases, such as Parkinson’s and even Alzhiemer’s. Often, scientists will create fruit flies that contain the same genetic mutations as seen in these disorders to see how the DNA changes affect the insects. Yet, for all the complex genetic tools they employ, the way of measuring the resulting motor defects remain crude: A researcher will knock the flies in a vial down to the bottom with a quick tap, and then wait to see how long it takes for the insects to climb to the top. (For an example, go to 2:28 into this video on LRRK2 animal models of Parkinson’s.)
Now, reporting in eLife, a team at Columbia University in New York has developed a more accurate and sophisticated way to quantify such movement. They first videotape a fly walking, and then, using computer software that can spot the individual footpads of the insect and mark when these each hit the surface. With this data, they can calculate the insects’ walking speed, distance covered and overall gait.