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Show Che Salt Lake Tribune L) COMICS * TV * LANDERS * MOVIES lo THURSDAY/May 1, 1997 breakiz. MONDAY:Time & Technology + TUESDAY:Outdoors ¢ Recreation : WEDNESDAY: Food & Garden . FRIDAY: Home & Family THURSDAY: Health & Science MUTANT FRO Scientists Link Deformities To Parasites, Pesticides BY DAVID REED THE ASSOCIATED PRESS STONY MAN MOUNTAIN, Va. — Inanisolat- ed mountaintop lodge with the lights turned down, 80 scientists from the United States and Canada clustered around a projector to view slides of misshapen, mutant frogs. What, they wanted to know, is causing the gross deformities turning up with alarming frequency in North America’s frogs? And if they are the victimsof a tainted environment, they wondered, can humans be far behind? Y Theylooked atfrogs with legs protruding from their stomachs andfrogs with no legsat all. They heard aboutfrogs with eyes staring disconcerting- ly from their backs and suction-cup fingers growing from their sides. Thecellular developmentof frogs and humans is very similar, said David Gardiner, a molecular biologist from the University of California at Irvine. “Maybe these frogs are pointing out that there is a more widespread problem,” said Kathy Con- verse of the National Wildlife Health Center. There have been reports of unusually high numbers of deformed frogs in Minnesota, Vermont, Wisconsin and Quebec. Clusters of deformedfrogs were also foundin California, Colorado, Idaho, Mississippi, Montana and Ohio. At an April meeting at Shenandoah National Park,scientists ranging from molecularbiologists to herpetologists examined theories that link the frog deformities to chemicals orparasites. “My best guess is that it has more to do with pesticides,” said Martin Ouellet of McGill University in Montreal. Ouellet and four other scientists have been studying deformed and normal frogs found in more than 100 pondsin the St. Lawrence River Valley the past four years. Normally, less than 1 percent of frogs are de- formed, and that’s about what Ouellet found in frogs taken from pristine ponds. But in ponds wherepesticides are used on surrounding land,as manyas 69 percent of the frogs were deformed, hesaid. Ifa pesticide is causing deformities,it’s probably a new brand because large numbers of frog deformities have not been noticed before, said Converse, of the Wildlife Health Center. “It's less likely to be oneof the older chemicals, like DDTor PCBs,”shesaid. Gardiner thinks that the deformities may be linked to a new generation of chemicals that mim- SCIENCE ‘The Associated Press Scientists are baffled by deformed frogs, such as this one with twoextra hind legs. What, researchers wonder,are implications for humans? ie growth hormones. The same kindof frog deformities that have been found in marshes and ponds — including extra legs and eyes — have been rep- licated in laboratory experiments, hesaid. “I can make a frog that looks like any frog you've seen at this meeting," said Gardiner, who specializes in cell regeneration. Scientists have induced the deformities with retinoic acid, a byproduct of a workhorse chemical called retinoid that is found in acne medicine and skin-rejuvenation creams. Retinoids powerfully effect development, and if they are inside a growing animal at the wrong place at the wrong time, they can cause deformities, he said. That’s why pregnant women are warnednotto use skin medicinesthat contain retinoids. Recent laboratory experiments have deter- mined that a pesticide can mimic a retinoid and, conceivably, cause defects in frog development, he said. “We should start screening chemicals, and we should start with pesticides, to see if they mimic naturally occurring retinoidsin the body,” Gardi- nersaid. Stan Sessions, a developmental biologist from Hartwick College, questioned whether a chemical could be the culprit because there were no deformed fish or other animals found in the ponds frog was missing a leg. Sessions told of a lab ex- periment in which he mimicked the invasion of parasites in a tadpole and caused it to sprout an extraleg as it developedinto a frog. “The mystery is beginning to resolveitself,” Sessions proclaimed. Someofhis colleagues were intrigued and said he was onto something. Butothers were skeptical. Finding the answer to the deformed-frog mystery will probably take three to five years of research, said Joe Tietge, conference organizer and where the deformedfrogs were captured. research biologist for the U.S. Environmental He believes parasites cause the deformities. Sessionsput a three-legged frog recently found in Vermont under a microscope and invited col- Protection Agency laboratory in Duluth, Minn. Onegoalof the meeting was to determine where research should be directed, said Tietge, the con- ic flatwormswere packedinto the joint where the and other federal agencies will award grants to scientists studying the phenomenon. leaguesto share in his discovery. In his partially dissected specimen,tiny parasit- ference organizer. At the end of May, the EPA Tourette Syndrome Still a Puzzle for Science MATTERS Pie CBE THESALT LAKE NE William McMahonhadjustfinished training as a child psychiatrist when he becameintrigued by the bizarre symptoms of a patient suffering Tourette syndrome. “It was an adolescent who had severe self-injury tics,” the doctor recalled nearly two decades later. The 13-year-old was incessantly beating himself. “I was both horrified and compelled to try to find out how to help.” McMahon's fascination would bloom into a career researching the mysterious neuropsychological disorder — including a search for the Tourette gene. “Thereare really two important features to my fascination — there seems to be a little Tourette in all of us, and the symptoms of involuntary movement or sounds seem to raise the ques- tion of what is free will," McMahon said The symptoms of Tourette — be- lieved to affect 40 in 100,000 children and four in 100,000 adults — range frommild tics and vocal noises to uncontrollable movements, compulsive barking, whooping and yelping. McMahon's theory on Tourette development centers onthe body's genetie code that dictates early stages of learning. “Whatever genetic components are part of Tourette, those genes probably code for learning by repetition,” he said, “Children, and adults as well, repeat what they see and hearand that's one of the most powerful mechanisms we have for learning.” McMahonwashonoredlast week for his research and educational efforts by the Utah Tourette SyndromeAssociation. He helped formthe ition and served as its medical adviser for years, ” Beth Raymond's son, Sean, 12, has ‘Steve Griffin/The Salt Lake Tribune Sean Raymond, 12 (with mother Beth Raymond), was diagnosed with Tourette syndrome at age 7. Medication has toned down symptoms. been one of McMahon's patients since he was diagnosed at age 7. “Hehad signs and symptomsall his life — uncontrollable body move- ments, vocal outbursts, But then he got worse. He developed into a totally different child," Raymondsaid, Sean began hurting himself and others. He was removed from school for behavioral problems and later hospitalized for a short time, Research shows some Tourette pa- tients have other disorders as well. McMahon determined Sean's condition was aggravated by obsessive-compul- sive (OC) disorder and severe depression. A mix of medications has toned down his symptoms. FRIDAY IN DAYBREAK: HOUSES BUILT OF STRAW “McMahonreally helped us," Raymond added. ‘He spenttime with us, gave us all the information and choices, We've learned so much about Tourette's. We've also learned compassion andpatience." In 1885, French neurologist Gilles de la Tourette identified the disease and described key symptoms as echo: lalia (repeating sounds) and echo- prexia (repeating gestures and movements). “If you watch an infant or listen to a toddler, you'll see a lot of echo move- ments and echo vocalizations,"’ McMahon said. “At some age, there is some See TOURETTE, Page C-8 |