Other therapies, Kurtzberg said, are just as likely to be developed by the time a child born today would contract many of the diseases advertised by the private banks.
'A LIFE PRESERVER THAT DIDN'T FLOAT'
The companies advertise that even without considering future scientific breakthroughs, there are many reasons to privately bank stem cells now.
Many companies list dozens of blood, bone and immune diseases — most of them genetic disorders or forms of leukemia.
But the chances of patients using their own banked stem cells for those purposes are slim.
The problem is that transplanting the cells can reintroduce the same genetic defect that caused the disease in the first place. Using a child's own cord blood to treat leukemia is also a problem, since it could include cancer cells — or would simply regenerate the same immune system that already had failed to destroy them.
Tracey and Victor Dones of Levittown, N.Y., learned this lesson the hard way.
In July 2002, Tracey gave birth to a son, Anthony, and banked his cord blood. Four months later, doctors at North Shore University Hospital in Manhasset, N.Y., diagnosed him with osteopetrosis, a genetic defect that triggers a runaway increase in bone density.
He would die without a stem cell transplant, they told his parents.
Tracey Dones quickly responded that an exact genetic match was waiting in a freezer tank in Florida.
"How perfect can this be?" she recalled thinking.
The doctors, though, explained that the stored blood was useless.
The cells were "a life preserver that didn't float," Victor Dones likes to say.
What finally saved Anthony was a parallel system of cord blood storage known as public banking.
These banks are typically nonprofit. They don't charge parents for harvesting or storing the cells. The public banks resemble blood banks, stockpiling donated cord blood and offering it to anybody in need of a transplant. The banks cover their costs by charging about $20,000 for each sample. As part of an accepted medical procedure, the blood is usually covered by insurance.
Because cord blood can be used with a lower degree of genetic matching than bone marrow transplants, it is ideal for transplants from unrelated donors.
In May, Congress voted 431-1 to spend $79 million to make searching easier by linking public cord blood banks in a national network.