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　　Scientists have mapped the genetic code of thetsetse fly, the insect responsible for African sleepingsickness. They said the findings could lead to betterrepellents and control efforts and boost vaccineresearch.

　　The World Health Organization reports African sleeping sickness occurs in 36 sub-Saharancountries. The bite of a tsetse fly transmits parasites that could eventually reach the centralnervous system causing confusion, sensory problems and poor coordination. It also disruptsthe sleep cycle giving the disease its name.

　　Dead tsetse flies are seen in a laboratory run by the International Livestock ResearchInstitute in Ghibe Valley, 115 miles southwest of Addis Ababa, Ethiopia, June 1, 2002. (AP Photo/Sayyid Azim)

　　The WHO said drug treatment is “complex,” but without it the disease is usually fatal. Effortsto control tsetse populations brought the number of new cases below 10,000 for the first timein 2009. In 2012, just over 7,200 new cases were reported.

　　Serap Aksoy is a professor of epidemiology of microbial diseases at the Yale School of PublicHealth. She and her colleagues in the U.S., Africa and elsewhere began searching the tsetse fly’sDNA for its genetic code 10 years ago. The WHO provided initial funding. In all, the projectcost $10 million.

　　“The genetic code is the blueprint of the fly that is responsible for making all the proteins thatare involved in all of its functions, essentially. These are involved in every aspect of the fly’sessential structure and function. They’re basically the parts list that an organism is madefrom,” said Aksoy.

　　African sleeping sickness is the name given when the disease affects people. When found inanimals it’s called Nagana.

　　“Sleeping sickness, along with Nagana, have hindered public health and development ofagriculture in Africa for centuries. This is a very neglected disease and hence limited amounts ofresearch funds have gone into the study of this insect and this disease. So, we’re really excitedthat this will be a breakthrough for control,” she said.

　　The genome could help researchers better understand just how functions within the tsetse flywork.

　　She said, “These included, for example, olfaction, which determines smell. What we callgustation, which is taste, vision, reproduction, digestion, blood feeding, immunity andsymbiosis. So, these were the kind of things, which we felt represented bottlenecks in [the] fly’sbiology. And as we decoded the genome we particularly looked for proteins involved in theseprocesses.”

　　Olfaction is important, for example, because one of the best ways to control the flies is withtraps. These traps use different scents to attract them.

　　“There are many such traps that have been developed for tsetse flies. But they are notnecessarily all efficient at the same rate and not available for some of the important speciesthat transmit the human disease. Scientists can now make better traps that would be moreefficient in attracting flies or they can make repellents that may be put on animals on people,”she said.

　　Aksoy said it’s not clear whether the research could lead to better treatment drugs. But, shesays, the information could help vaccine development. She added the research has led to thetraining of many young African scientists, who will further study the tsetse fly genome.

　　Genome research currently is underway for other parasitic diseases, including leishmaniasis,trypanosomiasis and Chagas.