Preimplantation genetic testing (PGT) began in 1968 when Gardner and Edwards [1] biopsied a rabbit blastocyst to perform X-chromatin analysis. The ultimate goal was to detect male embryos that would be excluded if at risk for X-linked recessive traits. However, not until human in vitro fertilization (IVF) was achieved in 1978, by Steptoe and Edwards [2], did applications to humans become imaginable. In that era, the methodology was known as preimplantation genetic diagnosis (PGD).
