NEWARK, Del., March 10 (UPI) -- U.S. and Italian researchers predict outer space will become a frequent tourist destination during this century.

"In the 21st century, space tourism could represent the most significant development experienced by the tourism industry," said University of Delaware Professor Fred DeMicco.

DeMicco, along with Professor Silvia Ciccarelli of the University of Rome -- a consultant to the Italian Association of Aerospace Industries -- said while there are global policies to be determined relating to private ventures in space, the technology to make space travel safer and cheaper is moving forward.

Ciccarelli said suborbital trips will likely be available to tourists by 2015, while tourism in space hotels is predicted to become a reality by 2025. She also noted the low-gravity of space will make possible novel recreational and sports activities that are impossible on Earth.

The study is to appear in the journal Hospitality Educator.

Progress reported in fragile X research

ATLANTA, March 10 (UPI) -- A U.S. team of scientists has identified several drugs and small molecules that reverse features of fragile X syndrome -- a form of mental retardation.

The scientists, led by Stephen Warren of Emory University, made their discoveries using a new drug screening method in Drosophila (fruit flies), setting the stage for development of new treatments for the syndrome, one of the leading known causes of autism.

Warren led a group of scientists that discovered in 1991 that the FMR1 gene is responsible for fragile X syndrome.

In the current experiment, scientists discovered when FMR1-deficient fly embryos were fed food containing increased levels of glutamate, they died during development.

The scientists placed the FMR1-deficient fly embryos in thousands of tiny wells containing food with glutamate. In addition, each well contained one compound from a library of 2,000 drugs and small molecules. Using that screening method, the scientists uncovered nine molecules that reversed the lethal effects of glutamate.

The study that included Shuang Chang, Steven Bray and Peng Jin of Emory, Zigang Li of the University of Chicago and Daniela Zarnescu from the University of Arizona appears online in the journal Nature Chemical Biology.

Endeavour is 'go' for Tuesday launch

WASHINGTON, March 10 (UPI) -- The U.S. space agency said all systems were "go" for the launch of space shuttle Endeavour and its STS-123 mission to the International Space Station.

The shuttle is to lift off at 2:29 a.m. EDT Tuesday from the Kennedy Space Center in Florida. The shuttle's seven astronauts will, among other things, deliver the first section of the Japanese-built Kibo laboratory and the Canadian Space Agency's two-armed robotic system called Dextre.

At 6 a.m. Monday, the rotating service structure that provides access and weather protection for Endeavour was retracted, clearing the way for loading about 500,000 gallons of liquid oxygen and liquid hydrogen propellants into the shuttle's external fuel tank Monday evening.

NASA said the weather forecast called for a 10 percent chance that atmospheric conditions would delay the launch, although meteorologists said they were concerned about the slight chance of a low cloud ceiling around Kennedy at launch time.

STS-123 will be commanded by Dominic Gorie with Gregory Johnson serving as shuttle pilot. The crew includes astronauts Rick Linnehan, Robert Behnken, Mike Foreman, Garrett Reisman and Japanese astronaut Takao Doi.

Common origins seen for clinical diagnoses

BALTIMORE, March 10 (UPI) -- A U.S.-led team of scientists has found two clinically different inherited syndromes are, in fact, variations of the same disorder.

Johns Hopkins University researchers studied Bardet-Biedl syndrome, which is characterized by a combination of vision loss, obesity, diabetes, extra digits and mental defects, and Meckel-Gruber syndrome, which is clinically distinct from Bardet-Biedl and generally associated with prenatal or newborn death.

They said their findings suggest, at least for those disorders, the total number and "strength" of genetic alterations an individual carries can generate a range of symptoms wide enough to appear like different conditions.

"We're finally beginning to blur the boundaries encompassing some of these diseases by showing they share the same molecular underpinnings," said Associate Professor Nicholas Katsanis. "This is important progress for several reasons. First, knowing what's going on molecularly and being able to integrate rarer conditions under common mechanisms allows us to potentially help more people at once.

"Second, clinicians can finally begin to offer more accurate diagnoses based on what really matters: the state of affairs at the cellular/biochemical level," he said.

The study that included scientists from France, Britain, Saudi Arabia, Israel and Uruguay appears in the April issue of Nature Genetics.