What if...? There are many phrases that could come after those two words, but many parents-to-be are now being actively asked to consider the question: what if their newborn child develops a serious disease, like cancer, later in life? Why? So that they can decide whether or not to bank their child's umbilical cord blood, a good source of haematopoietic stem cells, for future use.

There is little question that the use of cord blood for allogeneic bone marrow transplantation is as useful as (and some might argue better than) standard bone marrow transplantation for treating children and adults with a variety of diseases, including cancer. However, the key term in the sentence you just read, 'allogeneic,' and a lay definition are often missing from non-scientific reports about the utility of cord blood stem cells. This has important ramifications for public versus private banking of cord blood, as discussed by Michael Sullivan on p555 of this issue.

When commissioning this article for the journal, researching the information available on the Web on cord blood banking made for interesting reading. There is a good deal of hyperbolic literature about the potential of stem cells from cord blood to treat many ills, but interestingly the fact that these stem cells, whether haematopoietic or mesenchymal, are not the same as embryonic stem cells (that is, they are not pluripotent) is also often overlooked.

It is possible for those with a good scientific background to spot these discrepancies and make informed decisions, but it is not for the public at large. Private banking of umbilical cord blood is now big business thanks perhaps to a misunderstanding of the likely personal benefit or indeed use of the banked sample.