The Assisted Conception Unit at Guy's and St Thomas' NHS Foundation Trust is involved in various research projects. Below is a summary of some of the research currently being carried out.
1. The derivation of research and clinical grade stem cell lines.
When an embryo has developed correctly for 5 days we are able to see a collection of stem cells in its structure. Stem cells have the potential for developing into all the different types of tissue in the body. By studying stem cells in the laboratory researchers hope to be able to find out more about certain diseases and aim to be able to develop treatments for them. Stem cells are able to reproduce themselves in culture and therefore can be kept indefinitely in a Stem Cell Bank. As a condition of the licence for this project granted by the HFEA, a sample of any stem cell line created would be put into the national UK Stem Cell Bank and in this way they would be available for other researchers to access them, providing their research is approved.
2. Why is the success rate of assisted reproduction treatment so low?
As you are aware, the likelihood of pregnancy following assisted reproduction procedures is still low. During treatment there are often embryos which do not grow or develop properly. Sometimes cell division stops between the 4 and 8 cell stages of development and the embryo dies. An embryo would normally reach the 4 to 8 cell stage after 2 to 3 days of development and this is also the time that the embryo is usually transferred into the womb. In this project we are trying to find out why some embryos do not grow properly by looking at their genetic composition, examining the proteins the embryo makes and also the number of mitochondria inside each cell. Mitochondria are structures which provide the embryo with energy. It is possible that a defect in any one of these things can cause the embryo to die. We hope to develop sensitive tests which will enable easier identification of embryos which are more likely to implant and thus improve the success rate of assisted reproduction.
3. Pre-Implantation Diagnosis for genetic diseases
One in 100 babies is born with a serious genetic or chromosomal defect which can give rise to physical or mental abnormalities, pain and often early death. There are over 6,000 inherited disorders and most lack effective treatments. A recently developed technique now offers patients an alternative to chorionic villus sampling (CVS) or amniocentesis. The embryo can now be tested for a limited number of inherited diseases allowing only those embryos which are free of disease to be transferred into the womb. This technique is called Preimplantation Genetic Diagnosis (PGD). This research project aims to improve present techniques and expand the number of tests which can be undertaken. Most importantly we wish to develop methods which can ensure greater accuracy of the diagnostic procedures.