Genetic Testing of Embryos May Cause Dementia, Obesity In Adulthood

Monday, September 28, 2009 by: S. L. Baker, features writer
Tags: genetic testing, health news, Natural News

(NaturalNews) Preimplantation genetic diagnosis (PGD) has become an important part of the booming infertility and baby-making medical industry. This example of unnatural selection allows for the chromosomes of an embryo created through in vitro fertilization (IVF)to be analyzed. If there's a problem, the embryo can be discarded or, at the very least, frozen away. PGD has helped many couples conceive children believed to be totally healthy and the procedure is promoted as a widely used and safe medical test -- at least, until now. A new long-term analysis of PGD suggests that this procedure may hold serious long-term risks for humans subjected to this test while they were embryos. Animal tests have come up with worrisome evidence PGD could increase risks of obesity and dementia in adulthood.

Developed in the early 1990's, PGD is used so couples can prevent a pregnancy affected by a genetic condition or chromosomal disorder. It's performed by removing one or two cells (called blastomeres) for biopsy from the preimplantation embryo at the six to ten cell stage (about day three of development). If one or both parents-to-be have a known genetic abnormality and their child might be at increased risk for Tay Sachs disease, cystic fibrosis, muscular dystrophy, Fragile X syndrome, spinal muscular atrophy or other conditions, PGD can show if the embryo is likely to grow into a person with that potential problem. If that's the case, most like a decision will be made not to implant a specific embryo in a woman's womb.

While it's almost hard to believe, no rigorous long-term studies have been carried out in order to see whether PGD poses any serious health risks down the line -- even though the procedure involves manipulating a developing embryo. So Chinese scientists Ran Huo, Qi Zhou and colleagues decided to work with experiments in lab mice to examine how a blastomere biopsy, as the key manipulation used during the PGD procedure, actually impacts fetal, neonatal and adult development.

Their research, just published in the journal Molecular and Cellular Proteomics found there were no differences in embryo development prior to uterine implantation in the biopsied and control groups. However, successful births from biopsied embryos were significantly lower than in controls. As the mice grew after birth, the researchers looked to see if there were any differences in the bodies or behaviors of the animals that had experienced biopsies as embryos when compared tothose that had not been subjected to biopsies.

The results were disturbing. While the two groups of mice looked similar at first glance, the biopsied group of mice on average were fatter. What's more, they demonstrated significantly poorer memory in maze tests.

To try to find out what was going on, the scientists (who are based at Nanjing Medical University and the Chinese Academy of Sciences in Beijing) performed a detailed analysis of the adult mouse brains. In all, 36 proteins displayed significant differences between biopsied and control groups -- and 17 of these differences are closely associated with neurodegenerative disorders like Alzheimers and Down Syndrome.

Bottom line: the research team concluded that the developing nervous system may be sensitive to blastomere biopsy. They are calling for more studies to be performed in order to get to the bottom of any possible long-term adverse effects of PGD.

Editor's note: NaturalNews is opposed to the use of animals in medical experiments that expose them to harm. We present these findings in protest of the way in which they were acquired.

For more information:
http://www.mcponline.org/cgi/content/abstrac...
http://emedicine.medscape.com/article/273415...
http://www.reproductivegenetics.com/pgd.html
http://www.pubmedcentral.nih.gov/articlerend...