BOULDER, Colo., Nov. 29  -- A Colorado company is offering a new service for parents -- genetic testing to determine if they should steer their toddlers toward speed or endurance sports.

Atlas Sports Genetics in Boulder charges $149 to determine what variants a child carries of the ACTN3 gene, The New York Times reported Saturday. An Australian company, Genetic Technologies, has been offering the test since 2004.

As of Monday, Atlas will be marketing the test in the United States.

A 2003 study of elite athletes found that speed athletes were more likely to have two copies of the R variant of the gene, while endurance athletes were more likely to have two copies of the X.

But critics of such testing say the ACTN3 gene is one of about 200 that influence athletic performance.

Carl Foster, director of the human performance laboratory at the University of Wisconsin-La Crosse and one of the authors of the study, pointed to a Spanish Olympic long jumper who has no copies of the R variant. Foster suggested a more reliable way to determine children's athletic ability.

"Just line them up with their classmates for a race and see which ones are the fastest," he said. (UPI)