Preimplantation genetic diagnosis: present and future.
OBJECTIVE
Preimplantation genetic diagnosis (PGD) was developed more than a decade ago and aims to identify embryos free of genetic disease attributed either to gene mutations or chromosome errors. The purpose of this article is to provide an update on the current status and future prospects of PGD.


METHODS
Review of studies employing different strategies for the detection of single gene defects, and chromosome abnormalities, both structural and numerical in the context of PGD.


RESULTS
Amplification of several DNA fragments is feasible via multiplex PCR for the PGD of single gene disorders, whilst current FISH protocols employ up to 10 probes to identify embryos with a normal chromosome complement. New methods are being developed which will enable the assessment of the entire chromosome complement of embryonic blastomeres.


CONCLUSIONS
PGD has come a long way since its first application, and has become very accurate and reliable. Technical advances in the field of preimplantation genetics mean that PGD holds great promise for the future.
Fragouli
Elpida
E
Department of Obstetrics and Gynecology, Yale University Medical School, 300 George Street, Suite 770, New Haven, CT 06511, USA. ef242@email.med.yale.edu
D002869:Chromosome Aberrations; D020732:Cytogenetic Analysis / Q000379:methods; D005260:Female; D030342:Genetic Diseases, Inborn / Q000175:diagnosis; D006801:Humans; D011247:Pregnancy; D019836:Preimplantation Diagnosis / Q000379:methods / Q000639:trends*; D012730:Sex Chromosomes