Establishing the role of pre-implantation genetic diagnosis with human leucocyte antigen typing: what place do "saviour siblings" have in paediatric transplantation?

Background: Not all children in need of a haematopoietic stem cell transplant have a suitable relative or unrelated donor available. Recently, in vitro fertilisation (IVF) with pre-implantation genetic diagnosis (PGD) for human leucocyte antigen (HLA) tissue typing has been used to selectively transfer an IVF embryo in order to produce a child who may provide umbilical cord blood for transplantation to an ill sibling. Such children are sometimes called “saviour siblings”. Objective: To examine the published clinical and epidemiological evidence relevant to the use of this technology, with the aim of clarifying those situations where IVF and PGD for HLA typing should be discussed with parents of an ill child. Design: A critical analysis of published literature on comparative studies of umbilical cord blood versus other sources of stem cells for transplantation; comparative studies of matched unrelated donor versus matched related donor transplantation; and the likelihood of finding an unrelated stem cell donor. Conclusion: IVF and PGD for HLA typing is only applicable when transplantation is non-urgent and parents are of reproductive age. Discussions regarding this technology may be appropriate where no suitable related or unrelated donor is available for a child requiring a transplant, or where no suitable related donor is available and transplantation is only likely to be entertained with a matched sibling donor. Discussion may also be considered in the management of any child lacking a matched related donor who requires a non-urgent transplant or may require a transplant in the future.G N Samuel, K A Strong, I Kerridge, C F C Jordens, R A Ankeny, P J Sha