The clinical procedure known as PGD (preimplantation genetic diagnosis), essentially the diagnosis of genetic disease in IVF embryos, is now in its 25 year and Darren was one of its originators. In collaboration with Professor Alan Handyside (honorary at the University of Kent), Darren has recently been involved in development of a technique called “Karyomapping”. This approach essentially is a paradigm shift in the use of PGD from an approach where the genetic test had to be tailored to the disease in question to a near-universal assay applicable for most genetic diseases. The lab is also interested in how such diseases arise in human embryos, also through the study of human sperm and eggs. In addition to Kent based research Darren has developed a PhD programme where part time students can perform research in a satellite lab (e.g. in an IVF clinic) and discuss analysis and publication via electronic means. Alison Coates (Portland IVF, USA), Tyl Taylor (Charlotte, Virginia), Colleen Lynch (CARE Nottingham), Gary Harton (Illumina), are all past and present students on this programme. Companies and clinics involved include the London Women’s clinic, The Bridge Centre, Illumina, Genesis Genetics, and honorary Kent staff include Dr Alan Thornhill, Mr Michael Summers, Dr Vimal Vasu, Dr Christian Ottolini and Professor Nick Macklon.