Preimplantation diagnosis of genetic disease

Preimplantation diagnosis offers couples at high risk of transmitting a genetic disease the opportunity of prenatal diagnosis before the establishment of pregnancy. The successful application of embryo biopsy techniques, and of the polymerase chain reaction for the amplification of DNA, as well as fluorescent in-situ hybridization methods have allowed a small number of IVF units to identify the sex and/or genetic defect in human preimplantation embryos. The development of current methods being applied are reviewed. We suggest that there is a need for constant evaluation of the technique and for improvement of the present methods to ensure reproducibility and accuracy of the diagnostic procedures.