The American Medical Association supports the lawsuit.

Raising the ante in a high-stakes dispute, the American Medical Association has intervened in a lawsuit against Myriad Genetics and the University of Utah over the patenting of two human genes, arguing the practice limits women's health care options.

A hearing is set to begin today in federal court in New York in the action that poses a major challenge to the U.S. practice of granting patents on human genes, which supporters argue fosters research and treatments for disorders associated with particular genes.

Defendants are the University of Utah Research Foundation, the U.S. Patent and Trademark Office and Myriad Genetics, a Salt Lake City-based for-profit company that offers tests to determine if women have the two genes in question that are markers for increased risk of breast and ovarian cancer.

The AMA, a powerful group that represents the nation's doctors, joins an opposition that includes March of Dimes and more than a dozen other groups and that is being led by the American Civil Liberties Union.

The plaintiffs have "all said that genes are products of nature and they've also spoken about particular concerns relevant to the doctors and the parties they represent," said Sandra Park, an attorney with the ACLU Women's Rights Project.

At issue are two genes known as BRCA1 and BRCA2 that were researched at the University of Utah. About 15 years ago, the genes were licensed to Myriad Genetics, a company formed to create products from gene research. Myriad argues that the patents are necessary because they enable it to earn profits from research that leads to tests and treatments that otherwise might not be available.

But the AMA, in conjunction with the American Society of Human Genetics, American College of Obstetricians and Gynecologists, American College of Embryology and The Medical Society of the State of New York, argue in a court filing that patenting a natural part of the human body is unconstitutional and impedes medical research and treatments.

"Given that there are no substitutes for analyzing a patient's genetic makeup, the patent holder possesses a broad and unavoidable monopoly in the market for medical research, medical services and patient care," the groups said in a brief filed with the court.

U.S. District Judge Robert W. Sweet will hear arguments today on a motion to dismiss the case. The motion was filed by Myriad, the university and the Patent and Trademark Office.

They argue that those suing have failed to state how they have been or could be harmed by the patents and that, if the lawsuit goes forward, the case could undermine U.S. patent practices.

"This case is a thinly veiled attempt to challenge the validity of patents where, other than an overall policy disagreement concerning the legitimacy of gene patents, the plaintiffs have no actual dispute with the defendants over patent infringement," the university and Myriad said in their motion to dismiss. "If the plaintiffs in this case have standing, then virtually anyone can challenge any patent at any time."

But Katherine Drabiak-Syed of the Indiana University Center for Bioethics said a ruling against the researchers and women who brought suit could leave them and others like them with few options for challenging gene patents.

"If the court grants the defendants' motion or even finds plaintiffs have no standing, this could set a precedent that would effectively impede all other similarly situated affected researchers and individuals from using the judicial system as a vehicle for change in this area," she wrote in a paper set for publication in the Journal of International Biotechnology Law .

Who wants a say:

These groups asked to intervene in a lawsuit against Myriad Genetics and the University of Utah Research Foundation over the patenting of human genes.

March of Dimes

Claire Altman Heine Foundation Inc.

Massachusetts Breast Cancer Coalition

National Organization for Rare Disorders

National Tay-Sachs & Allied Diseases Association

American Medical Association

American Society of Human Genetics

American College of Obstetricians and Gynecologists

American College of Embryology

Medical Society of the State of New York

National Women's Health Network

Asian Communities for Reproductive Justice

Center for Genetics and Society

Generations Ahead

Pro-Choice Alliance for Responsible Research

International Center for Technology Assessment