The Supreme Court has ruled that human DNA cannot be patented, and the researchers whose lawsuit prompted the decision were celebrating on Thursday.

"I think it changes everything," Dr. Harry Ostrer, a genetics expert at Albert Einstein College of Medicine in New York , told NBC News.

"I think this is a green light for us to go ahead with our testing," he added. "It will drive down costs and improve quality."

The American Civil Liberties Union, which backed Ostrer in the suit, said many more patents on genetic tests may also fall. "Obviously, we are thrilled with the decision, " said the ACLU's Sandra Park.

"This ruling is a victory," Park told reporters in a conference call.

Ostrer is one of those who sued Myriad Genetics over the company's strict enforcement of its patents on two cancer-related genes - BRCA1 and BRCA2. Ostrer said the company's legal threats have kept researchers like himself from making and distributing DNA tests that can test multiple genes at a time to tell someone their cancer risk.

"You won't need to get prior approval from Myriad Genetics to have the BRCA1 and 2 results reported," Ostrer said.

The Court ruled that natural DNA cannot be patented, and that no matter how clever Myriad was in finding the particular gene mutations it did, or in removing and copying that DNA to make a test, it cannot claim a patent on the DNA itself.

The unanimous ruling makes a point of saying Myriad's patent was on a product, not a method. "Had Myriad created an innovative method of manipulating genes while searching for the BRCA1 and BRCA2 genes, it could possibly have sought a method patent," reads the ruling, written by Justice Clarence Thomas. But it used well-known and reported methods.

Ostrer says what the ruling does is protect other aspects of the biotech industry - those that use artificial and engineered DNA to make drugs, for instance. "The biotech industry had expressed a lot of concern that they would lose out," Ostrer said.

Kevin Noonan, a partner at Chicago law firm McDonnell Boehnen Hulbert & Berghoff LLP, who specializes in the biotechnology industry, says most gene tests don't look at the entire gene anyway any more. Newer tests can look at small bits of the the gene, just looking for the important mutations that affect cancer or other disease risk.

"If you don't get the whole gene isolated in a test tube, you don't infringe the claim," Noonan.