CLEVELAND, Nov. 12 (UPI) -- U.S. medical researchers report they have determined the genetic basis for some birth defects that affect the development of the heart and head.

A multidisciplinary team led by Case Western Reserve University Professor Gary Landreth discovered a common genetic pathway for a number of birth defects such as abnormal development of the jaw, palate and brain.

The researchers said they developed a mouse model of the disorders by removing a gene, ERK2, responsible for the pathway. The scientists, in collaboration with Dr. William Snider at the University of North Carolina, discovered the mice missing the gene for ERK2 in neural crest cells had developmental defects resembling those of human patients with a deletion that includes that gene.

Landreth, with Case Western Associate Professor Michiko Watanabe, found the mouse hearts had characteristic defects resembling those seen in the patients with ERK2 deletions.

"Given Dr. Watanabe's findings, we determined that we had in fact developed animal models that mimicked the human deletion syndrome," said Landreth. "This work sheds light on how these developmental errors occur."

The research that included Dr. Sulagna Saitta at the Children's Hospital of Philadelphia appears in the Proceedings of the National Academy of Science.

Infrared Aurora discovered on Saturn

PASADENA, Calif., Nov. 12 (UPI) -- The U.S. space agency's Cassini spacecraft has detected an aurora that lights Saturn's polar cap unlike any other planetary aurora known in our solar system.

National Aeronautics and Space Administration scientists said the aurora was detected by one of the infrared instruments aboard Cassini.

"We've never seen an aurora like this elsewhere," said Tom Stallard, a scientist working with Cassini data at Britain's University of Leicester. "It's not just a ring of auroras like those we've seen at Jupiter or Earth. This aurora covers an enormous area across the pole. Our current ideas on what forms Saturn's aurora predict that this region should be empty, so finding such a bright aurora here is a fantastic surprise."

NASA said the new infrared aurora appears in a region hidden from the Hubble Space Telescope, which has provided views of Saturn's ultraviolet aurora. Scientists said the new aurora is constantly changing, even disappearing within a 45 minute-period.

Stallard is lead author of a paper reporting the aurora that appears in the journal Nature.

Brain activity linked to menstrual changes

BLOOMINGTON, Ind., Nov. 12 (UPI) -- U.S. scientists have determined strong brain activity in the brains of women viewing masculinized male faces is most pronounced when they're ovulating.

Researchers at Indiana University's Kinsey Institute said it's been known a woman's preferences for masculine characteristics in men changes during the menstrual cycle. Through the new study, the scientists wanted to determine if those changes were linked with changes in brain activity.

Neuroscientist Heather Rupp and her team used computer imaging software to masculinize and feminize 56 male faces. The faces were shown to 12 heterosexual women with an average age of 25 years during a time they were close to ovulation, and during the luteal phase that begins after ovulation.

The researchers collected blood samples for hormone analyses and used functional MRI to measure brain activity in several brain regions.

The findings showed stronger responses to masculinized than feminized faces in brain regions related to face perception, decision making and reward processing when the women were closer to ovulation, the researchers said.

The study appears in the online edition of the journal Evolution and Human Behavior.

Butterflies, spiders go into outer space

BOULDER, Colo., Nov. 12 (UPI) -- University of Colorado-Boulder scientists are sending a group of butterflies and spiders into space aboard the U.S. space agency's shuttle Endeavour.

The educational payload of spiders and butterflies destined for the National Aeronautics and Space Administration's International Space Station will be closely monitored by hundreds of elementary and high school students from Colorado.

The two educational experiments that will be aboard Endeavour on its scheduled Friday launch from the Kennedy Space Center were designed and built at the school's BioServe Space Technologies department.

BioServe Director Louis Stodieck, principal investigator of the NASA-funded projects, said one will be used to compare how "space" spiders differ from Earth spiders in web spinning and feeding. The second experiment will chart the life cycle of butterflies in the low gravity of space -- from larvae to pupa to butterfly to egg -- and compare that cycle with that of earthbound butterflies.

More than a dozen middle schools from Colorado's Front Range will be participating in the educational project.

"This program is an excellent example of using a national asset like the International Space Station to inspire K-12 students in science, technology, engineering and math," Stodieck said.