PGD-PCR possible outcomes
No embryo transfer
Not all embryos may be suitable for biopsy. They may however, be suitable for freezing or transfer .
An answer is achieved for over 99% of all embryos tested. For technical reasons, we may not get an answer on an individual embryo and the genetic status of that embryo will be unknown. These embryos may still be suitable for clinical use.
No embryos with desired genetics
Embryos tested and deemed abnormal or affected are unsuitable for transfer.
Whilst we take extra precautions against DNA contamination, there is always a small risk that this may result in a misdiagnosis. PCR will copy any DNA present - the DNA copied should only be from the biopsied cells.
Other technical factors may contribute to loss of genetic information that might result in misinterpretation of the genetic status of the embryo.
Preferential Amplification and Allele Drop-out
DNA may copy unevenly which could cause difficulty in interpreting the results. This potential outcome is controlled by tests that look at multiple regions around the gene.
Chromosomes naturally rearrange their DNA and this may affect the interpretation of the result. If a mutation test is also included this may resolve the problem.
The above factors vary from test to test and may lead to a reduction in accuracy. If this occurs during your treatment it will be discussed with you by your PGD scientist.