A federal law banning compensation for organ transplants doesn't extend to bone marrow harvested from a donor's blood, a federal appeals court has ruled. The decision could attract thousands of new donors in a national campaign to save the lives of those afflicted with cancer, leukemia and genetic disorders.

The 1984 National Organ Transplant Act included bone marrow in its list of "organs and parts thereof" for which donors could face criminal charges and five years in prison for providing them in exchange for money or other "valuable consideration."

Although bone marrow is naturally replenishable, unlike livers, kidneys and other whole organs, its sale was barred because the extraction method used at the time the law was passed was painful and risky for the donor and authorities feared the poor would be induced to submit to the procedure to earn money.

In the past 20 years, though, medical advances have brought about a less intrusive method by which the life-saving marrow stem cells are harvested from a donor's bloodstream in much the same way as blood is drawn at a blood bank.

"This is a fundamental change to how deadly blood diseases will be treated in the country," said Jeff Rowes, the Institute for Justice attorney who argued the case before the 9th Circuit panel in February. "Compensation will expand the donor pool by at least hundreds and potentially thousands each year."

More than 3,000 Americans die each year waiting for a marrow donor, Rowes said.