Preimplantation genetic diagnosis

ABSTRACT

Preimplantation genetic diagnosis (PGD) is a technique to examine genetic disease or chromosome abnormalities in single cell biopsied from embryos before implantation to uterus. It allows achieving normal pregnancy by transfer of unaffected embryos. The main indications are single gene disorders and recurrent miscarriage related to chromosome aberration and it has advantages to avoid termination of pregnancy or miscarriages in couples with high risk. PGD is also widely applied for aneuploidy screening in assisted reproduction to improve the outcome in infertile patients such as advanced maternal age, although its efficacy still needs to be established. Furthermore, the application of PGD has expanded to other indications, such as late onset-diseases with genetic predisposition and human leukocyte antigen typing for stem cell transplantation. With the advances of molecular diagnostic technologies using single cells, such as fluorescent in situ hybridization, multiplex polymerase chain reaction, fluorescent polymerase chain reaction, linkage analysis, whole genome amplification, array comparative genomic hybridization (array comparative genomic hybridization), and next generation sequencing, PGD can provide more comprehensive and reliable diagnosis.