Experts Question WADA Blood Test for HGH
Catlin wants more research data on current ‘isoform’ test
Sonksen criticizes officials, touts his ‘marker’ test for growth hormone
By Matt Chaney
Posted Sunday, March 21, 2010
Preeminent anti-doping scientists are citing problems about the Olympic “isoform” test for synthetic human growth hormone, in response to the ongoing campaign of WADA and USADA officials who want pro sports like baseball to adopt their controversial blood scan.
“It is simply not a useful test, no matter how you cut it or spin it,” said American testing engineer Don H. Catlin, M.D., director of the non-profit Anti-Doping Research laboratory, speaking in a telephone interview last week from Los Angeles.
Catlin said he hasn’t seen “any scientific discussion” on the blood scan’s disputed reliability, only “warfare” rhetoric exchanged through media, pitting anti-doping officials against administrators of sports and unions.
In London, England, growth-hormone testing pioneer Peter H. Sonksen, M.D., says WADA officials erred years ago by casting aside his bio-marker scan, going instead with the assay for GH isomers. Sonksen says his bio-marker system can confirm artificial GH in the bloodstream for as long as two weeks, while the isoform’s detection window lasts about 24 hours.
“I don’t know why they chose the isoform,” Sonksen said of anti-doping officials in a webcam interview. “I think they thought this was a more direct test than our marker method. I think that they were, ah, too thick to understand it. They weren’t experts in the field, and they don’t really understand it. The isoform test would be every bit as difficult to defend in court as our method.”
Sonksen receives research funding from the anti-doping agencies, including their parent WADA. Major League Baseball and the Amgen biotechnology firm fund Catlin’s work, among his current grants.
WADA officials administer and market the long-standing GH isoform test, which only recently returned a positive result leading to suspension of an athlete, British rugby player Terry Newton, who did not contest the finding.
That positive result, announced Feb. 22, was the first confirmed among about 1,500 tests conducted since the 2004 Olympics. WADA and USADA hail the development as proof of the isoform method’s validity and reliability.
But Catlin dismissed that claim for the present, maintaining too little is known about the isoform for proper review by independent science. He is confident WADA has conducted clinical trials on subjects, presumably including athletes, but no scientists have the data outside those employed within agency “working groups,” as officials term the closed network.
“I believe they have data,” Catlin said. “I mean, it would be silly not to. But they don’t display it.”
Echoing Catlin, American sport officials argue the WADA test for growth hormone needs scientific airing in public. When MLB and union officials recently reiterated the call, WADA president John Fahey replied “nonsense” to their charge of inappropriateness about the test.
“If I were baseball, I’d want to see the [research] numbers,” Catlin said, “but WADA won’t show the numbers. They recognize, rightfully, that as soon as they do show the numbers, there could be difficulty.”
Sonksen, Catlin and other scientists say WADA practice to limit information on the isoform model dates to its patenting a decade ago by German researcher Christian J. Strasburger, M.D., who became an in-house scientist of the agency. Previous to the test’s launching six years ago, a WADA spokesperson told ABC Science Online that “we won’t comment on specifics and, for obvious deterrence reasons, we won’t give those details even when a test is in place.”
Charles E. Yesalis, Sc.D., historian and researcher on doping, rebuked the WADA blockade on testing information. “I’m just astounded,” said Yesalis, the epidemiologist and Penn State professor emeritus who co-authored the first comprehensive surveys of teen steroid use in the United States.
Yesalis contends sport anti-doping technology must be more precise than many standard medical tests, since a positive finding virtually assures punitive consequence for the athlete. “It’s almost criminal. I mean, if you’re going to ruin somebody’s life, and if you don’t have [credible testing] totally locked up, to me that is immoral and unethical. I’d rather see five million cheaters compete than see scientists bastardizing themselves.
“And this has been going on since that testosterone ratio test,” Yesalis said, noting the epitestosterone-testosterone assay, introduced in 1983, that has been debunked for reliability by recent studies and statistics review--yet remains in use by anti-doping agencies.
Yesalis posed an analogy to illustrate the disregard for scientific convention: “If you and I had a proprietary laboratory, and we did a press conference where we said we just had a major breakthrough in a screening test for cancer. And we just said, ‘Well, you’ve got to trust us.’
“Well, immediately other epidemiologists would ask, ‘What’s your sensitivity and specificity? What’s the percent of positives that are truly positive, and what’s the percent of negatives that are truly negative? And please show us exactly how you do this test so we can replicate it.’
“If you couldn’t answer those questions, you’d be laughed out of the scientific community. I’ve said this for years, about the way they behave [anti-doping officials]. Yeah, they do publish some stuff, but it’s very difficult to understand, historically.”
Among concerns, Catlin says establishing precise baseline for human GH secretion is problematic and unverified by scientific consensus. The concept of isoform testing relies on a consistent GH baseline to pinpoint amounts of the dominant isomer known as 22kDa—or molecular weight in kilodaltons—when it’s suppressed by presence of identical versions that are synthetic or “recombinant” growth hormone. Natural GH pulsates irregularly in the human body while activity, gender, age and ethnicity also spur levels to fluctuate.
And Catlin wants to know more about the test before he would implement the protocol in his own laboratory, particularly for the prospect of defending it in court, including against affluent athletes and unions likely to contest positive findings of recombinant growth hormone.
Sonksen believes the isoform is reliable for readings within 24 hours of rHGH introduction to a body physiology, if a sampling captures enough of the synthetic drug. But he said the specter of court challenge looms, even if the first-case Newton chose to confess his illicit use.
“I think there’s a certain fear amongst the, ah, [WADA] politicians that if it comes to a case in court, they won’t win it,” Sonksen said, adding the isoform has undergone little modification since 2004. “You only have to go to [engineers] Strasburger and [Martin] Bidlingmaier, and see how many papers they’ve published on the subject. Most of them are reruns of their original papers.
“There’s very little new [data], and I think it would be quite easy for a lawyer to drive a cart and horses through it in court.”
Sonksen does believe WADA would win a court test of the isoform method. But he contends the agency should strengthen its testing by finally implementing his serum-marker detection for growth hormone, which over time builds a profile of an athlete’s natural levels in “outcome” substances like insulin growth factor-1 and collagens. He says his test in complement with Strasburger’s isoform model would produce effective prevention against GH doping by athletes.
WADA has considered Sonksen’s HGH test before, but put it aside for every Olympics since the 2000 Sydney Games, perplexing him and more experts worldwide, such as Catlin. They say the marker method has credible peer review in scientific publication.
Sonksen and WADA have often battled in public over their differences.
Catlin intoned: “I’m a great fan of [marker testing]. It should be done. But, again, there’s all the publicity that goes around this. Now, Peter Sonksen has said some pretty tough things to WADA, but I think he’s rightfully saying them because the [isoform] test alone doesn’t work. It’s political. This whole thing’s political.”
Sonksen is optimistic his test will be adopted for the 2012 London Olympics on his home turf, and he claims backing by U.K. Anti-Doping officials. But he’s wary of the WADA administration.
“Yes, they’re politicians, aren’t they,” he surmised. “They’re sports politicians, not scientists, although they’ve got scientific training. Their interest is in the politics of sport.”
Matt Chaney is a journalist, editor, teacher and publisher in Missouri, USA. E-mail him at email@example.com. For more information, including about his 2009 book Spiral of Denial: Muscle Doping in American Football, visit the home page at www.fourwallspublishing.com.