Gulf War syndrome linked to enzyme level

Gulf War syndrome linked to enzyme level

By TROY GOODMAN

DALLAS (June 21, 1999 12:10 a.m. EDT http://www.nandotimes.com) - Soldiers born with low levels of an enzyme that helps the body fight off chemical toxins are more likely to report symptoms of Gulf War syndrome than soldiers born with normal levels, according to a new study published in Toxicology and Applied Pharmacology.

The authors say the small-scale study of 46 Gulf War veterans is the first to suggest a genetic marker to explain why some soldiers got sick from possible exposure to toxic nerve agents, possibly in combination with pesticides.

Thousands of veterans returned from the 1990-91 war in the Middle East complaining of chronic, unexplained health woes. The veterans said they are experiencing confusion, memory loss and balance problems. Others said they have pain in their neck, shoulders and hips, the researchers said.

"Now we know that there's a genetic reason why some of these guys got sick and others didn't," said Dr. Robert Haley, the chief of epidemiology at the University of Texas Southwestern Medical Center in Dallas and the study's author.

His findings, which appeared in the June 16 issue of Toxicology and Applied Pharmacology, are based on a larger 1997 study of a Naval Mobile Construction Battalion, or Seabees.

Haley, with assistance from Dr. Bert La Du and Scott Billecke from the University of Michigan Medical School, investigated how the Seabees' genes produced an enzyme in their bodies that naturally protect them from toxins. Those born with low levels of the protective enzyme - called type Q paraoxonase, or PON-Q - were the ones who reportedly got sick.

Twenty-one of the 26 sick Seabees in the study had below average or extremely low PON-Q levels in their blood. Haley said the enzyme levels are constant throughout a person's life and likely wouldn't be lowered because of illness.

"The PON gene is a good candidate" for signaling neurological damage resulting from chemical or nerve gas exposure, said Dr. Simon Wessely, a Gulf War researcher at King's College at the University of London, who was not involved with the study. "But any findings like this must be regarded as preliminary."

Haley agreed, calling his findings a "highly refined hypothesis."

"We spent $3 million on these 46 guys and so we've been able to measure the things that are likely to be the cause of their illness," Haley said. "Now it's time to move on."

The Department of Defense and the Perot Foundation provided funding for the study.

Haley and Wessely both noted that larger studies are under way to examine the link between PON levels and war-related illness.

More than 697,000 Americans served in the Gulf War that succeeded in driving Iraqi forces out of Kuwait in 1991.

Sick veterans suggest they were exposed to chemical pollutants from burning oil fields, insecticides or inoculations to protect them from germ warfare. They also say they were possibly exposed to Iraqi chemical or biological weapons, infectious diseases and depleted uranium used in artillery shells.

The Pentagon asserts there's no conclusive evidence to support those claims but says it has not ruled out chemical or environmental explanations and continues to investigate.

In January, a large study of British troops found that soldiers who served in the Gulf War do have a rate of general ill health - at least two times as high as troops who went to Bosnia and soldiers who stayed home.

But that study by Wessely and others cautioned that there was no single "syndrome" among the ill soldiers.

Haley's previous research on a small number of patients concluded that some Gulf War veterans suffer from distinct symptom clusters caused by chemical poisoning and that some may have suffered neurological damage from nerve gas or pesticides.