Pre-Implantation Genetic Diagnosis Risk

A Neurologic Question Mark over Genetic Screening

Jul 26, 2009

New research has cast more doubt over pre-implantation genetic diagnosis after it was discovered that mice suffer neurological damage when born after the technique.

PGD is an increasingly common technique in IVF, used to screen out chromosomally abnormal embryos, including those that suffer from gender related health conditions. The embryo is fertilized in a lab and a small biopsy taken so that its cells can be checked for things like Down Syndrome and HMSN.

Many healthy children have been born following this technique, who may have suffered debilitating or life-threatening illnesses without it, but doctors at the Laboratory of Reproductive Medicine, Nanjig Medical University in China, have tested the procedure on mice and found that it increases the risk of abnormally excessive weight gain and memory loss.

PGD has always been thought to be safe, but researchers have done very little study into the affects of blastomere biopsy on the health of the infant.

There were no differences in the implantation rate between the two groups, mirroring the findings with human beings, but the successful birth rate was much lower in the group who had had a biopsy as part of PGD.

A Future with Alzheimers?

Although the two groups of mice were very similar in a lot of areas, Dr. Huo found that the biopsied mice were heavier in weight and had poorer memory than those who had not.

To obtain a more in depth understanding of the cause, the research team then analysed the mouse brains and found that 36 brain proteins were 'significantly different' in the group who had undergone PGD, and 17 of those proteins were associated with Alzheimers disease and other degenerative neurological conditions, spelling a potential time bomb for children born after PGD.

The team hypothisized that the nervous system could be sensitive to blastomere biopsy and that more research should be undertaken to determine its safety.

As mice are not similar to human beings and animals are known to react differently to drugs and treatments, then maybe the next step is to study the population of children born after PGD to see if they are at higher risk from neurological disorders?

Meanwhile, potential parents should be warned that safety studies are still ongoing, before they decide whether or not to have screening.

Source: Evaluation of Blastomere Biopsy Using a Mouse Model Indicates the Potential High...

The copyright of the article Pre-Implantation Genetic Diagnosis Risk in Infertility is owned by Joanna Karpasea-Jones. Permission to republish Pre-Implantation Genetic Diagnosis Risk in print or online must be granted by the author in writing.