Current Status of Preimplantation Genetic Diagnosis

Since its first clinical application in early 90s, preimplantation genetic diagnosis (PGD) hasbecame a powerful diagnostic procedure in clinical practice for avoiding the birth of an affectedchild as well as increasing the assisted reproductive technologies (ART) outcome. The techniqueinvolves the screening of preimplantation embryos for chromosomal abnormalities in certainindications such as advanced maternal age, repeated abortions and translocations, or for single genedefects, the majority of which are cystic fibrosis and thalassaemias. In this context, it becomes analternative option for traditional prenatal diagnosis. So far, more than 1000 unaffected babies havebeen born after PGD, indicating that the procedure is safe and effective in prevention of geneticdefects as well as increasing the ART outcome. Besides its diagnostic value and expandingindications such as cancer predisposition, dynamic mutations and late onset disorders, a newfeature, namely preimplantation human leuckocyte antigen (HLA) typing also demonstrates itsnovel therapeutic role in contemporary medicine. This article summarizes the recent status of PGDand discusses the current limitations and future perspectives associated with PGD techniques.