PGD: Preimplantation Genetic Diagnosis
Embryos can be genetically tested prior to transfer back to the mother. Tests currently used require viable cell DNA which can be obtained from an embryo starting from Day 3. The cells inside an embryo are called blastomeres and there are about 8 blastomeres in a Day 3 embryo. Each of the 8 blastomeres has the potential and genetic material to form a complete human being. As seen in identical twins transferring each of the 8 blastomeres to a separate person can result in 8 babies. Thus one or two blastomeres from a Day 3 embryo can be taken out for genetic testing, this procedure is called Embryo Biopsy. Genetic testing can be performed at an earlier stage embryo by removing and testing the Polar Body. The embryo at its later stages are called Blastocysts and Blastocyst Biopsy can be performed to remove a cluster of cells for genetic testing. Cells removed after the biopsies are tested using the FISH and PCR techniques
Preconception Gender Selection
This method is used in conjunction with standard IVF treatment. A cell is removed for testing from the embryos that form as a result of the treatment. FISH or PCR is used to ascertain the cell’s genetic make-up and embryos are selected accordingly. Healthy embryos or those with genetic mutations are identified through this method. The selected embryos are transferred back the mother one or two days later.