Molecular genetic analysis of single cells.

Preimplantation genetic diagnosis (PGD) has experienced a considerable technical evolution since its first application in the early 1990s. The technology for single-cell genetic analysis has reached an extremely high level of accuracy and enabled the possibility of performing multiple diagnoses from one cell. Diagnosis of a monogenic disease can now be combined with aneuploidy screening, human leukocyte antigen typing, and DNA fingerprinting. New technologies such as microarrays are opening the way for an increasing number of serious genetic defects to be detected in preimplantation embryos. The new PGD techniques will empower patients and clinicians to screen for almost any kind of genetic problem in embryos, with the potential to change completely the manner in which parents approach and manage genetic disease.