Preimplantation genetic diagnosis: an overview and recent advances

Key content Preimplantation genetic diagnosis (PGD) was developed for couples at risk of transmitting a genetic disorder to their children. Before PGD, options available to these couples were remaining childless, prenatal diagnosis, gamete donation or adoption. Couples requesting PGD have in vitro fertilisation (IVF) to produce embryos for biopsy, even if they are fertile. Learning objectives To understand indications for PGD. To learn about the genetic work up required prior to undergoing IVF. To learn about IVF, embryogenesis, the biopsy process and when to transfer disease-free/carrier embryo(s). Ethical issues PGD for ‘saviour sibling’: should couples be offered human leucocyte antigen (HLA) matched treatment for a child who is in remission or who may develop the late onset condition? PGD for sex selection: should we offer sex selection for ‘family balancing’?