Monday, March 21, 2016

tiny lab monkeys but without the guilt

The husband of a dear friend (hi MK and Andy!) recently challenged me to incorporate a fruit fly into an illustration. Obviously, I made a hipster fruit fly logo because that’s what everyone has been missing in their lives. A few folks asked me what the G, T, C, and A meant in the illustration – so, here it is.

Drosophila melanogaster is a species of fruit fly that has been used as a model organism in labs for about a hundred years, like tiny lab monkeys but without the guilt. In 1909, an entomologist named Charles Woodworth suggested they be used to study genetics, kind of like Gregor Mendel used pea plants. Woodworth’s idea was brilliant.

Drosophila are sexually dimorphic, meaning it’s easy to tell males from females by appearance. This is useful when it comes time to mate them. Secondly, they have only four chromosomes, which are easily observed during times of genetic activity. They have several discreet physical traits that are genetically determined, like eye color, wing shape, bristles, and body color. They breed quickly and a lot- allowing people to observe multiple generations in a reasonable amount of time. Lastly, they’re easy and cheap to maintain. They’re frickin fruit flies.

For decades people have been studying these guys. They’ve given us insight into how basic genetics, beyond the white or red pea plant blooms, operate in a system founded on DNA. In 2000, we completed sequencing the entire genome of Drosophila melanogaster- that is, the sequence of 139,500,000 G’s, C’s, T’s, and A’s that make a fruit fly a fruit fly.

Not only can you look up every single nitrogenous base (G, C, T, or A) present in a red-eyed, black-bodied, curly-winged, bristleless fruit fly, you can look up where those genes reside, what sequences control them, and what bits of DNA don’t do anything.

One might ask what good it does to have such an intimate genetic knowledge of a fruit fly, and one might be totally justified in asking that question. The answer is this: 75% of known human genes that cause disease are present in the fruit fly’s genome. About 50% of their coding DNA also codes in us. By studying the fruit fly’s genome, we’re studying how things like diabetes and cancer work. And that’s important.

So if you haven’t hugged a fruit fly today… don’t. They smell weird. But do tell it thank you for its service to science.

No comments:

Post a Comment